http://book.klll.cc/ebooks/subject/31907.opds 2025-08-22T22:17:18Z Books about Addition -- Juvenile literature (sorted by popularity) Free eBooks since 1971. Project Gutenberg https://book.klll.cc webmaster@gutenberg.org https://book.klll.cc/gutenberg/favicon.ico 25 1 2025-08-22T22:17:18Z https://book.klll.cc/ebooks/56127.opds Die Thurmuhr: eine Rechen-Fibel für kleine Kinder (German) F. G. Normann