Andrey Stamatin's Blueprints

Andrey Stamatin's Blueprints is a quest item in Pathologic found in the Bachelor route.

On Day 11, the Bachelor obtains this item as part of the main quest "The Foundation of a Miracle".

Quote
"A supplement to the Polyhedron blueprints. They describe the terrible foundation which allows the Tower to stand, defying the laws of physics and geometry. The supplement also contains all the relevant calculations."