INDENYL AND FLUORENYL TRANSITION METAL COMPLEXES. IV. REACTIONS OF 2- AND 4-AZAFLUORENES WITH CHROMIUM HEXACARBONYL Статья Thoma T., Pleshakov V.G., Prostakov N.S., Ustynyuk Yu.A., Nesmeyanov A.N., Ustynyuk N.A. Journal of Organometallic Chemistry. Том 192. 1980. С. 359-365