World Wide Fund for Nature, 1978 - 2012, cancelled collection with good issues like Michel no. Burundi 1596 / 08, Chile 986 / 87, Malawi 297 / 300 and pages 52, South Georgia 203 / 06Zw and Surinam 1517 / 19Zw, as well different sheet and sheetlet, in 2 albums, high catalog value