Drafts of three publications by R.P. Ambler including Evidence for the amino acid sequences of the "small" cytochromes C2 from three species of purple phototrophic bacteria, Evidence for the amino acid sequences of the zinc-requiring beta lactamase II from two strains of the Gram-positive bacterium Bacillus cereus (5/B/6 and 569/H), and Evidence for the amino acid sequences of the cytochromes C3 from several species of sulphate reducing and other bacteria.