On Second Order Linear Differential Equations with Few Transcendental Solutions. Hans Peter Rehm — 1986 Manuscripta mathematica
Galois groups and elementary solutions of some linear differential equations. Hans Peter Rehm — 1979 Journal für die reine und angewandte Mathematik
Prime factorization of integral Cayley octaves Hans Peter Rehm — 1993 Annales de la Faculté des sciences de Toulouse : Mathématiques