For administrative queries, please contact M.M. Ravelli:

Visiting address:
Sterrenwachtlaan 11
2311 GW Leiden

Postal address:
Postbus 778
2300 AT Leiden

T: +31-(0)71-527-7748

E: gro.r1747700098ivnk@1747700098tcatn1747700098oc1747700098

To contact the Secretary of the Board of the Society, please send an email to gro.r1747700098ivnk@1747700098draob1747700098.