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kempner.net
Kempner, Joshua (2022). «KEMPNER Cosmology Calculator». Kempner.net. Ανακτήθηκε στις 6 Αυγούστου 2022. KEMP Cosmology Calculator - Set H0=67.4 and OmegaM=0.315 (see Table/Planck2018 at "Lambda-CDM model#Parameters")