Nepal, Mount Everest Expedition 1972. 3 covers addressed to Dr Dermann, Germany, originating from the German Everest/ Shlotse Himalayan expedition of 1972. One is airmail book post and another cover has a letter signed by Gerhard Lenser, expedition leader. two covers have special cachets from the HQ in Kathmandu. Estimate  $150 - 200. $0