1. We cannot say for sure whether the landlord at this time was Pieter Willem de Zwart, or his son Michiel Antonie de Zwart. We assume that it was the latter: a few letters addressed to him have survived.
2. Here Van Gogh spells the name ‘Giesenberg’, but in letter 412 it is ‘Kiezenberg’. The person in question is Willem Kiesenberg. He lived at Schenkweg 134 (later Schenkstraat 15), very close to Van Gogh. See Visser 1973, pp. 23-30.