Details about the experimental sources on ¹²CH spectroscopy excluded during this study, with reason given for the exclusion.

Source	Reason for exclusion
00Amano96	Criticised by 13TrHeHiTa102 as having large systematic errors.
08JaZiMcPe100	No extractable data; focuses on magnetic resonance.
14TrHeToHi103	Data provided by 13TrHeToLe.20
19MaRoBrMu104	Modelling/experimental study with no extractable data.
56KiBr64	Data are superceded with those from more accurate sources.
65BlNi65	No extractable data available from this source.
71BaBr67	Data are superceded with those from more accurate sources.
74RyElIrSu69	Astronomical measurement of lower accuracy than laboratory determinations.
78HoMuHeEv70	Data are superceded with those from more accurate sources.
83BrEv75	Only Hamiltonian parameters are provided.
83BrBr74	Calculated data only.
88LyWo85	No transitions data provided.
88NeBrEv86	Only Hamiltonian parameters are provided.
90NeBrEv88	Only Hamiltonian parameters are provided.
91GrLaSaVa11	No transitions data provided.