关于其背景信息,参见非美国版权之解释。 The Swiss copyright on Mittelholzer's work's expired at the end of 1987, since Switzerland had a copyright term of 50 years p.m.a. until 1993, and the extension to 70 years p.m.a. made in 1993 did not restore already expired copyrights.
{{Information |Description= Hurden und Seedamm Rapperswil, 1929, Blick nach Osten, Aufnahme von Walter Mittelholzer (1894 - 1937) |Source= Die Schweiz von damals, Flugaufnahmen von Walter Mittelholzer, Weltbild-Verlag, Olten 2005 |Date=1929, upload Dezem