@Book{Bopp1978,
author  = "Bopp, Fritz",
title   = "Ein streng lösbares Teilproblem der Quantenelektrodynamik",
year    = "1978",
address = "München",
series  = "Sitzungsberichte",
volume  = "1977,7",
url     = "https://publikationen.badw.de/en/003384281",
}