malitson_1965#
I. H. Malitson, “Interspecimen Comparison of the Refractive Index of Fused Silica”, J. Opt. Soc. Am. 55, 1205 (1965)
Source record · Catalogue · Review register
Source kind: measurement
Recorded technique: Minimum deviation on 60-degree prisms (faces about 4.5 cm square) of optical-quality fused silica from three makers, four production runs each: Corning code 7940, Dynasil high-purity synthetic fused silica and General Electric type 151 (p. 1205). Three prisms, one per maker, were measured at 60 wavelengths, 0.2139-3.7067 um (emission lines and absorption bands, Table I), on the NBS instrument of Rodney and Spindler (1954), at ‘controlled room temperatures near 20 degrees C’, with a single Golay cell (CaF2 window) as detector; Table II’s note calls it the Gaertner spectrometer. All twelve prisms were measured at 20 degrees C at 18 wavelengths, 0.4047-1.08 um, on a Wild precision spectrometer with an infrared image converter (pp. 1207-1208). dn/dT from repeated measurements at 30 degrees C on the General Electric prism (p. 1209).
Materials in structured entries: SiO2
Dataset quantities: refractive_index, refractive_index_deviation
Contents: 17 datasets; 1 formula.
Curation notes#
Journal pages 1205-1209 are pdf pages 1-5. Identity checked against the first page.
WAVELENGTHS. Table I lists each line with its source (Zn, Cd, Hg, H, He, Na, Cs, and absorption bands of 1,2,4-trichlorobenzene (TCB) and polystyrene (Poly) in the infrared). The wavelengths are the lines’ standard-air wavelengths: Hg 0.546074 um is the green line whose vacuum wavelength, 546.2258 nm, the gas records use (e.g. peck_1966, borzsonyi_2008). They are recorded as standard air (TC-326). In the infrared, beyond about 2.2 um, ‘the wavelength accuracy is not exactly known since atmospheric water-vapor bands were superposed on the absorption spectra of the wavelength standards’ (p. 1207). At 0.226747 um the residual ‘would change to +28 x 10^-6 if the wavelength used was 0.226624 u’, the average of the Cd line 0.226502 u and the assigned wavelength (p. 1207).
INDEX. The paper does not say whether the index is relative to air (the minimum deviation was measured in air) or reduced to vacuum; it gives no air correction. Presumably relative to air at 20 degrees C, the convention of glass catalogues; to be settled (TC-326).
ACCURACY. ‘an average absolute residual of 10.5 x 10^-6 indicates that values of index may be interpolated by means of the dispersion equation to five significant decimal places’ (p. 1207); the largest residuals are at both ends of the range (wide slits in the ultraviolet; wavelength identification in the infrared). The Wild measurements: ‘+-5 x 10^-6 for 14 visible lines and +-20 x 10^-6 for 4 near infrared wavelengths’ (pp. 1207-1208), level not stated. Index gradients of the material: 0.9-1.6 x 10^-5 cm^-1 (5 cm x 5 cm x 1 cm samples, p. 1205).
TABLE I. The ‘C-D-G.E.’ column is the residual of an ‘arithmetical-mean table of values compiled from experimental data of Corning (C), Dynasil (D), and General Electric (G.E.)’ (footnote a), to which Eq. (1) was fitted. It is not the average of the three specimen columns printed beside it: at 0.213856 um it is -27 against -29, -42, -31 (average -34); at 0.237833 um +1 against +13, +23, +19; at 1.81307 um +21 against -7, -7, +6 (a finding; the paper does not say how the mean table was compiled). Averages of the absolute residuals (last row, not extracted): 10.5 (mean), 11.9 (Corning), 12.2 (Dynasil), 11.7 (General Electric). The library cells read the Corning column’s header factor as 10^9; the image prints 10^6 (structural fix in the extraction script).
TABLE II. Residuals (units of 1e-6; measured minus Eq. (1)) of the twelve prisms at 9 of the 18 wavelengths. ‘Av. Delta n’, the average over all 18 wavelengths, per prism (Corning 1-4: 13.5, 24.9, 20.0, 21.6; Dynasil 1-4: 3.5, 27.4, 20.4, 20.5; General Electric 1-4: 11.3, 12.9, -9.6, 13.2) and the nu-values (67.77-67.88) are not per wavelength and are kept here only. Specimen 1 of each brand is the Table I prism, measured again on the Wild spectrometer: ‘This accounts for differences in residuals between tables.’ ‘the maximum index variation for specimens from the same source is 11, 24, and 23 units in the sixth decimal place for Corning, Dynasil, and General Electric’ (p. 1207); the lower indexes ‘suggest that the variations are caused mainly by small temperature gradients which exist during the annealing’, not impurities (p. 1208).
FIGURES (not digitised). Fig. 1: n against wavelength, 0.2-4 um, dashed over 2.4-3.2 um where the OH band prevents measurement. Fig. 2: the relative dispersion (-dn/dlambda)/(n - 1), minimum near 1.3 um, and its reciprocal. Fig. 3: dn/dT for 20-30 degrees C (mean 25 degrees C), General Electric prism: ‘about 15 x 10^-6/degree C at 0.21 u to about 10 x 10^-6/degree C at 0.4 u’, constant through the visible, ‘about 12 x 10^-6/degree C at 2.0 u, then decreases to 10 x 10^-6/degree C at 3.7 u’ (p. 1209). Fig. 4: Rodney and Spindler’s (1954) values, adjusted to 20 degrees C, minus Eq. (1): +8e-5 at 0.34 um, +2e-5 from 0.56 to 1.4 um, +8e-5 at 3.5 um (p. 1209). Transmission (p. 1205): about 92 % from near 0.2 um to 3.5 um for 1 mm, OH band at 2.7 um (minimum about 10 %), overtones at 2.2 and 1.4 um; cutoffs near 0.16 and 4.5 um for 1 cm.
Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.
Datasets#
malitson_1965/computed#
{
"id": "computed",
"material": "SiO2",
"file": "SiO2/malitson_1965__computed.csv",
"table": "tbl_b692ffe8e259",
"quantity": "refractive_index",
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "check",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"temperature_k": 293.15,
"form": "bulk"
}
}
Table I, ‘Computed index’: Eq. (1) at the 60 wavelengths, the formula’s own column. The measured index is this plus a residual column.
malitson_1965/residual_mean#
{
"id": "residual_mean",
"material": "SiO2",
"file": "SiO2/malitson_1965__residual_mean.csv",
"table": "tbl_b692ffe8e259",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "check",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
}
}
Table I, ‘C-D-G.E. residual x 10^6’: the arithmetical-mean table of the three prisms minus Eq. (1), the data the formula was fitted to. Compiled from the same prisms as the three specimen columns (though not their average: see the source notes), so it is a check beside them, not fitted with them.
malitson_1965/residual_corning_7940#
{
"id": "residual_corning_7940",
"material": "SiO2",
"file": "SiO2/malitson_1965__residual_corning_7940.csv",
"table": "tbl_b692ffe8e259",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Corning 7940",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
}
}
Table I, Corning 7940 residual x 10^6 (measured minus Eq. (1)): one prism (Corning code 7940 fused silica; specimen 1 of Table II), Gaertner spectrometer, 60 wavelengths. The library cells read the header factor as 10^9; the image prints 10^6 (structural fix).
malitson_1965/residual_dynasil#
{
"id": "residual_dynasil",
"material": "SiO2",
"file": "SiO2/malitson_1965__residual_dynasil.csv",
"table": "tbl_b692ffe8e259",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Dynasil",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
}
}
Table I, Dynasil residual x 10^6 (measured minus Eq. (1)): one prism (Dynasil high-purity synthetic fused silica; specimen 1 of Table II), Gaertner spectrometer, 60 wavelengths.
malitson_1965/residual_ge_151#
{
"id": "residual_ge_151",
"material": "SiO2",
"file": "SiO2/malitson_1965__residual_ge_151.csv",
"table": "tbl_b692ffe8e259",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "General Electric type 151",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
}
}
Table I, General Electric type 151 residual x 10^6 (measured minus Eq. (1)): one prism (General Electric type 151; specimen 1 of Table II), Gaertner spectrometer, 60 wavelengths.
malitson_1965/specimen_corning_7940_1#
{
"id": "specimen_corning_7940_1",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_corning_7940_1.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Corning 7940",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, Corning 7940 specimen 1: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes. Specimen 1 is the Table I prism, measured again on the Wild spectrometer; its residuals differ from Table I’s at the same wavelengths.
malitson_1965/specimen_corning_7940_2#
{
"id": "specimen_corning_7940_2",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_corning_7940_2.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Corning 7940",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, Corning 7940 specimen 2: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes.
malitson_1965/specimen_corning_7940_3#
{
"id": "specimen_corning_7940_3",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_corning_7940_3.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Corning 7940",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, Corning 7940 specimen 3: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes.
malitson_1965/specimen_corning_7940_4#
{
"id": "specimen_corning_7940_4",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_corning_7940_4.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Corning 7940",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, Corning 7940 specimen 4: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes.
malitson_1965/specimen_dynasil_1#
{
"id": "specimen_dynasil_1",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_dynasil_1.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Dynasil",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, Dynasil specimen 1: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes. Specimen 1 is the Table I prism, measured again on the Wild spectrometer; its residuals differ from Table I’s at the same wavelengths.
malitson_1965/specimen_dynasil_2#
{
"id": "specimen_dynasil_2",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_dynasil_2.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Dynasil",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, Dynasil specimen 2: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes.
malitson_1965/specimen_dynasil_3#
{
"id": "specimen_dynasil_3",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_dynasil_3.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Dynasil",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, Dynasil specimen 3: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes.
malitson_1965/specimen_dynasil_4#
{
"id": "specimen_dynasil_4",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_dynasil_4.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "Dynasil",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, Dynasil specimen 4: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes.
malitson_1965/specimen_ge_151_1#
{
"id": "specimen_ge_151_1",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_ge_151_1.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "General Electric type 151",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, General Electric type 151 specimen 1: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes. Specimen 1 is the Table I prism, measured again on the Wild spectrometer; its residuals differ from Table I’s at the same wavelengths.
malitson_1965/specimen_ge_151_2#
{
"id": "specimen_ge_151_2",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_ge_151_2.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "General Electric type 151",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, General Electric type 151 specimen 2: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes.
malitson_1965/specimen_ge_151_3#
{
"id": "specimen_ge_151_3",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_ge_151_3.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "General Electric type 151",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, General Electric type 151 specimen 3: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes.
malitson_1965/specimen_ge_151_4#
{
"id": "specimen_ge_151_4",
"material": "SiO2",
"file": "SiO2/malitson_1965__specimen_ge_151_4.csv",
"table": "tbl_46b93cc0e194",
"quantity": "refractive_index_deviation",
"scale": 1e-06,
"abscissa_unit": "um",
"wavelength_medium": "standard_air",
"use": "primary",
"parameters": {
"index_medium": "air",
"air_temperature_k": 293.15,
"reference": "malitson_1965/sellmeier",
"grade": "General Electric type 151",
"temperature_k": 293.15,
"form": "bulk",
"technique": "minimum deviation"
},
"uncertainty": {
"column": true,
"level": "not stated"
}
}
Table II, General Electric type 151 specimen 4: residual x 10^6 (measured minus Eq. (1)) at 9 of the 18 wavelengths, Wild spectrometer, 20 degrees C; the sigma column is the stated +-5 (visible) or +-20 (0.8944-1.083 um) x 1e-6; the average over the 18 wavelengths is in the source notes.
Formulas#
malitson_1965/sellmeier#
{
"id": "sellmeier",
"form": "n2_sellmeier_wavelength",
"terms": {
"B": [
"0.6961663",
"0.4079426",
"0.8974794"
],
"L": [
"0.0684043",
"0.1162414",
"9.896161"
]
},
"wavelength_medium": "standard_air",
"index_medium": "air",
"air_temperature_k": 293.15,
"range_nm": [
213.92,
3707.72
],
"material": "SiO2",
"equation": "Eq. (1), p. 1207 (also the abstract, p. 1205)",
"printed": "n^2 - 1 = 0.6961663 lambda^2/[lambda^2 - (0.0684043)^2] + 0.4079426 lambda^2/[lambda^2 - (0.1162414)^2] + 0.8974794 lambda^2/[lambda^2 - (9.896161)^2]",
"variable": "lambda: wavelength in um, the standard-air wavelengths of Table I (see notes)",
"range": "0.2139-3.7067 um (the 60 wavelengths fitted), 20 degrees C; 'valid for interpolation to five decimal places over the measured wavelength range' (Fig. 1 caption)",
"coefficients": {
"B1": "0.6961663",
"lambda1": "0.0684043",
"B2": "0.4079426",
"lambda2": "0.1162414",
"B3": "0.8974794",
"lambda3": "9.896161"
},
"check": "Reproduces Table I's computed index at all 60 wavelengths to within 8.3e-7 (six decimals printed; the differences of 5-8e-7 follow from the rounding of the printed coefficients). Checked 2026-09-26."
}
Printed with the resonance wavelengths lambda_i, kept as printed (form n2_sellmeier_wavelength, C_i = L_i^2). Fitted by least squares (Sutton and Stavroudis) to the arithmetical-mean table of the three prisms; average absolute residual 10.5e-6. The index is relative to the room air of the measurement: the paper does not say so, but Leviton & Frey (leviton_2008, pp. 3, 9) read it as ‘in air’ and, so converted, agree with their absolute indices to ‘well less than 1e-5’ (TC-326, TC-399). tan_1998 finds its interferometric n at 3-6.7 um ‘exactly equal’ to the formula’s extrapolation (errors within +-5e-4 in the 3-3.7 um overlap, ~1e-3 overall); kitamura_2007 and arosa_2020 reproduce the coefficients (Arosa rounded to four digits).
Corrections#
No dataset errata are recorded in this source record.
Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the review register for the checks and decisions.