Synthesis of (3aR*,6aR*)-2,2,5,6-Tetramethyl-1,2,3,3a,4,6a-hexahydropentalene: A Potential Precursor of Protoilludane Sesquiterpenes - Fitjer, Lutz; Gerke, Ralf; Anger, Thorsten (Synthesis, 1994)