Duden, Konrad
"Vollständiges Orthographisches Wörterbuch der deutschen Sprache" by Konrad Duden is a spelling dictionary first published on July 7, 1880. This foundational work gathered 27,000 entries on 187 pages and became the basis for standardized German spelling across the German Empire. The dictionary evolved through numerous editions, navigating political divisions and linguistic changes. After World War II, separate East and West German versions emerged, each reflecting their societies' vocabularies while attempting to preserve unified orthographic standards until reunification. (This is an automatically generated summary.)
These books are free to read. Each is in the public domain in the United States; check your own country's rules before you copy or share one.