Project Gutenberg 2010-06-25 Public domain in the USA. 218 Blackburn, Hugh 1823 1909 Elements of Plane Trigonometry For the use of the junior class of mathematics in the University of Glasgow en Plane trigonometry QA Text Mathematics Browsing: Mathematics Browsing: Science - General 635680 2010-06-25T11:17:27 application/pdf 465276 2010-06-25T11:17:27 application/pdf application/zip 277311 2021-06-11T17:20:30 application/prs.tex 181406 2021-06-11T17:20:30 application/prs.tex application/zip 9719 2025-06-13T11:54:32.513979 application/rdf+xml 13852 2025-06-13T11:54:32.442949 image/jpeg 3415 2025-06-13T11:54:32.175027 image/jpeg Archives containing the RDF files for *all* our books can be downloaded at https://book.klll.cc/wiki/Gutenberg:Feeds#The_Complete_Project_Gutenberg_Catalog en.wikipedia