Netherlands West Indies. (Suriname). 1940. Registered Air Mail envelope addressed to Luxembourg bearing Suriname Yvert 186, 2 1/2 (+2)c green, Yvert 187, 3 (+2)c orange, Yvert 188, 5 (+3)c blue and Yvert 189, 7 1/2 (+5)c carmine tied by Paramaribo date stamp '9th May 40' with matching registration label with 'Geopend Door de Censur' censor tape routed via Trinidad '14th May' with oval 'Registered/ London' in violet on reverse '13 Jul' with framed instructional 'No Service/ Returned To Sender' on face and endorsed 'Dutch Guiana' with Paramaribo '13th Aug 40' on reverse. Luxembourg was occupied by the Germans May 10th 1940 and so the mail was interrupted and returned. Superb item.