How many letters does the top answer for “author of the knights of the cross” have?

The most common answer is sienkiewicz (11 letters).

Crossword clue: author of the knights of the cross

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

sienkiewicz 11 letters wd-fact-v3

author of princess knight 50% similar → tezuka

author of the nonexistent knight 50% similar → calvino

author of the seventh cross 50% similar → zinnemann

wrote the knights of the cross 50% similar → sienkiewicz