NETHERLANDS → RHODESIA KLM flight cover for the centenary of “Dingaansdag” (later termed “Geloftedag” and “Day of the Vow”) with 5 Dec 1938 Amsterdam Centraal Station datestamps, “EEUWFEEST DINGAANSDAG” purple cachet of 6 Dec 1938 and Voortrekkermonument (Pretoria) 14 Dec 1938 datestamps on front and back.