Sphaera mundi
Sacro Bosco, Joannes de, active 1230; Regiomontanus, Joannes, ...
Meditations
Marcus Aurelius
The Hard Thing About Hard Things
Ben Horowitz
Game Engine Gems 2
Eric Lengyel
Hypercomplex Numbers: An Elementary Introduction to Algebras
I. L. Kantor & A. S. Solodovnikov