REDUCTION OF QUATERNARY SALTS OF 3-AZAFLUORENE AND 3-AZAFLUORENONE AND THEIR CONVERSION TO INDENOINDOLIZINES ArticleProstakov N.S., Soldatenkov A.T., Radzhan P.K., Samal'oa A., Zakharov V.F., Zvolinskii V.P.Chemistry of Heterocyclic Compounds. Том 19. 1983. С. 206-209
