Variations - Invoice - First Part: Treatises by Joh. Bernoulli, Jac. Bernoulli, and Leonhard Euler is an unaltered, high-quality reprint of the original edition from 1894. Hansebooks is a publisher of literature on various topics such as research and science, travel and expeditions, cooking and nutrition, medicine, and other genres. The focus of the publisher is on preserving historical literature. Many works by historical writers and scientists are now only available as antiques. Hansebooks reissues these books, contributing to the preservation of rare literature and historical knowledge for the future.