Master list (pdf) of all 602 L-numbers, their Leeuwenhoek number, and their Collected Letters number
Full title:
Brief van G: Bidloo, aan Antony van Leeuwenhoek; wegens de dieren, welke men zomtyds in de lever der schaapen en andere beesten vind
Letter of G. Bidloo to Antony van Leeuwenhoek; concerning the animals, which are sometimes found in the liver of sheep and other beasts