Title: Geometries
Subjects: Textbooks, History and biography -- History of mathematics and mathematicians -- 19th century, History and biography -- History of mathematics and mathematicians -- Greek, Roman, Geometry, Category theory; homological algebra -- Instructional exposition (textbooks, tutorial papers, etc.)., Geometry -- Research exposition (monographs, survey articles), Geometry -- Instructional exposition (textbooks, tutorial papers, etc.)., Category theory; homological algebra -- Instructional exposition (textbooks, tutorial papers, etc.), Geometry -- Instructional exposition (textbooks, tutorial papers, etc.)