Memberships
- Fellow of the Royal Geographical Society of Great Britain
- Member and honorary member of the Koninklijk Nederlandsch Aardrijkskundig Genootschap (Royal Netherlands Geographical Society)
- Member and Director of the Hollandsche Akademie van Wetenschappen
- Member of the Maatschappij der Nederlandsche Letterkunde (Netherlands Literary Society)
- Member and board member of the Nederlandsche Zuid-Afrikaansche Vereeniging (Netherlands - South African Society)
- Honorary member of the Nederlandsche Vereeniging voor den Volkszang (Dutch Society for the Propagation of Community Singing)
- Member of the freemason's lodge Hiram Abiff in The Hague (1897-?) (possibly only briefly)
- Member of the Nieuwe of Littéraire Sociëteit De Witte (New or Literary Club De 'Witte') in The Hague 1894-1941
Read more about this topic: Hendrik Pieter Nicolaas Muller