Pure Appl. Chem., 1972, Vol. 31, No. 4, pp. 639-646
http://dx.doi.org/10.1351/pac197231040639
IUPAC-IUB COMMISSION ON BIOCHEMICAL NOMENCLATURE
A One-letter Notation for Amino Acid Sequences (Definitive Rules)
First page:
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Pure Appl. Chem., 1972, Vol. 31, No. 4, pp. 639-646
http://dx.doi.org/10.1351/pac197231040639