"A fraction is the ratio of one constitutent (part) to all constituents of a mixture. [Allotrope]" . "fraction" . "2020-06-22 Changed labels. [Allotrope]" . . "Green Book, 2nd ed.: IUPAC Quantities, Units and Symbols in Physical Chemistry. Second Edition, Blackwell Scientific Publications, Oxford, 1993." . . "fraction" . "Definition pending. [0]" . "true"^^ . . . "fraction (quality)" . .