SUBSTITUTED PYRIDINES. 2, 5-DIAROYL-4-PHENYLPYRIDINES AND 2, 5-DIAMINO-4-PHENYLPYRIDINES СтатьяProstakov N.S., Banerdzhi S.K., Rodes L.G.Chemistry of Heterocyclic Compounds. Том 4. 1970. С. 205-206