Gmelin Handbook of Inorganic and Organometallic Chemistry - 8th edition
Maple
Gmelins Handbuch der Anorganischen Chemie
Gmelins Handbuch der Anorganischen Chemie
8. Aufl. 1937
Glocking / Krüerke / Siebert
Tetraorganogermanium Compounds from Ge(C3H7)3R' to GeRR'R¿R¿, Germacyclic Compounds, and Organogermanium Compounds with Low-Coordinate Germanium Atoms
8th ed. 1990
Krüerke
Part C 3: Binuclear Compounds 3
8th ed. 1980