Geneste, P., Kamenka, JM., Roques, R., Declercq, J.-P., & Germain, G. (1981). An Axial Tert-butyl Group - Crystal-structure of 1-phenyl-c-4-tert-butyl-r-cyclohexylpiperidine Hydrochloride. Tetrahedron Letters, 22(10), 949-950. https://doi.org/10.1016/0040-4039(81)89016-8 (Original work published 1981)