Esperanto - Stamp Centenary - Airmail
S.A.T. Esperanto Congress Amsterdam
F.L.E. Esperanto Congress Heerlen
Esperanto Domo Arnhem
Esperanto F.L.E. Heerlen
I.K.U.E. Esperanto Congress The Hague
Esperanto - S.A.T. Congress Amsterdam
Esperanto - S.A.T. Congress Rotterdam
International Esperanto Congress Haarlem
Esperanto Congress Haarlem
Esperanto Jubilee Congress
Esperanto Congress
Esperanto - 100 years of international language
Esperanto
Esperanto - S.A.T. Congress Amersfoort
Esperanto Congress Oostende