@Book{Bopp1970,
author  = "Bopp, Fritz",
title   = "Wechselwirkung durch Symmetriebrechung in der Quantenmechanik",
year    = "1970",
address = "München",
series  = "Sitzungsberichte",
volume  = "1969,5",
url     = "https://publikationen.badw.de/de/003454778",
}