Frydman, R.B., Tomaro, M.L. and Frydman, B. (1972). „Pyrrolooxygenase: its action on tryptophan-containing enzymes and peptides”. Biochim. Biophys. Acta284: 80-89. PMID4403729.
Camoretti-Mercado, B. and Frydman, R.B. (1986). „Separation of tryptophan pyrrolooxygenase into three molecular forms. A study of their substrate specificities using tryptophyl-containing peptides and proteins”. Eur. J. Biochem.156: 317-325. PMID3699018.
