Rybkin, N. A. Collection of Stereometric Problems Requiring the Use of Trigonometry (Sobranie stereometricheskikh zadach, trebuyushchikh primeneniya trigonometrii), 1915. In Russian.

Рыбкин Н. А. Собрание стереометрических задач, требующих применения тригонометрии. / 14-е издание.
Москва : Типография Г. Лисснера и Д. Собко, 1915.
IV, 80 с. : черт. ; Обычный формат. Твердый переплет.
***
Rybkin, Nikolay. Collection of Stereometric Problems Requiring the Use of Trigonometry. / 14th edition.
Moscow : Typography of G. Lissner and D. Sobko, 1915.
IV, 80 pp. : diagr. ; Regular format. Hardcover.

This 1915 edition represents the pinnacle of pre-revolutionary Russian pedagogical excellence, authored by the renowned mathematician and educator Nikolay Alexandrovich Rybkin. As the 14th edition of this specialized collection, the book reflects the enduring stability and effectiveness of Rybkin's methodology, which remained the gold standard for geometry and trigonometry instruction well into the late 1970s. The work is specifically designed for high school students and candidates for higher technical education, focusing on complex three-dimensional problems—stereometry—that necessitate the application of trigonometric functions. The text provides a deep dive into the internal logic of spatial geometry, including the arrangement of polyhedrons, bodies of revolution, and the calculation of surface areas and volumes using sine and cosine laws.
The volume was printed in Moscow by the prominent Typography of G. Lissner and D. Sobko, known for producing high-quality academic and technical literature during the late Imperial period. Rybkin's textbooks were celebrated for their rigorous logical structure and the progressive difficulty of the problems presented. Across 80 pages of text and numerous technical drawings (чертежи), the author bridges the gap between abstract Euclidean geometry and practical computational mathematics. This specific 1915 printing is an important primary source for the history of mathematics education in Russia, capturing the educational standards of the era just before the revolutionary transitions of 1917. For collectors of scientific ephemera and pedagogical history, this hardcover edition stands as a testament to the longevity of Rybkin’s intellectual legacy.