BBA 475(1):14;1977; Biochim Biophys Acta 390:192;1975; Can J Microbiol 23(5):626;1977; Environ Qual Safety 5:49;1976; Int J Cancer 20:296;1977; J Antibiot 29(5):595;1976; J Antiobiotics 29(12):1341;1976; J. Antibiotics 30(11):1019;1977; Mol Gen Genetics 154(1):67;1977