Orographic map of the Aare Glacier, Illustration of the Aargletscher from the 19th century, signed: dessin? par J.R. Stengel, Ingr, Neuch?tel, Suisse, Lithog., Sonrel;, Pl. III, p. 22, 23, 26 & 27, Stengel, J. R. (des.); Sonrel, A. (lith.), 1846, Lou