http://book.klll.cc/ebooks/author/36912.opds?sort_order=downloads 2025-11-15T14:28:42Z Books by Perry, John Free eBooks since 1971. Project Gutenberg https://book.klll.cc webmaster@gutenberg.org https://book.klll.cc/gutenberg/favicon.ico 25 1 2025-11-15T14:28:42Z https://en.wikipedia.org/wiki/John_Perry_(engineer) See also: en.wikipedia 2025-11-15T14:28:42Z https://book.klll.cc/ebooks/34268.opds Spinning Tops John Perry