Ruhe in Frieden, Hans Erni. A Swiss graphic designer and artist, Erni designed (among other things) about 90 postage stamps in his career, including the above beauties. He died on this date in 2015 at the whopping age of 106.
Stamp details: Stamps on top: Issued on: August 28, 1969 From: Vaduz, Liechtenstein SC #454-457
Middle stamp: Issued on: March 9, 1964 From: Bern, Switzerland SC #435
Stamps on bottom: Issued on: May 29, 2984 From: United Nations Office, New York SC #423-424
Paul Klee (Swiss, 1879, 1940), Baum Kultur (Tree Culture), 1924, watercolor and oil transfer drawing on paper, with watercolor on cardboard mount, 47.4 x 34.9 cm, New York, Solomon R. Guggenheim Museum
Paul Klee (German, born Switzerland. 1879–1940), Forest (Wald) from the periodical Münchner Blätter für Dichtung und Graphik, 1919, Lithograph from a periodical with five lithographs, 16.7 x 12.5 cm, New York, Museum of Modern Art