https://petersen-fegetasch.de/
Willkommen bei Hans Peter Petersen Landtechnik aus Fegetasch bei Kappeln
Herzlich willkommen bei Hans Peter Petersen Landtechnik
willkommen beihans peterpetersenlandtechnikaus
https://journals.ub.uni-heidelberg.de/index.php/fc/article/view/99829
Zum Abschied von Peter Petersen | Forum Classicum
zum abschiedpeter petersenvonforum
https://digitalcollections.lib.iastate.edu/iou/items/iou742.html
Woodward H. Brown letter to Peter C. Petersen regarding Audubon field notes, December 9, 1964 |...
Item from Iowa Ornithologists' Union Collection: Audubon field notes were contributed by Woodward H. Brown in a letter to Peter C. Petersen. This item was used...
https://digitalcollections.lib.iastate.edu/iou/items/iou755.html
Pearl Knoop letter to Peter C. Petersen regarding nesting season, August 21, 1964 | Iowa...
Item from Iowa Ornithologists' Union Collection: Report of nesting season in Marble Rock, Iowa was contributed by Pearl Knoop in a letter to Peter C. Petersen....