Volumes 1 through 20 of Alle de Brieven / Collected Letters, the complete series. Download for free.
Master list (pdf) of all 602 L-numbers, their Leeuwenhoek number, and their Collected Letters number
full title
Kohier van de huishoudens binnen de gerechten en ambachten onder Delft ressorterende, 1680
aka Kohier Familiegeld, Family Estate Notebook