Алгол (звезда) — разлика између измена

* {{Cite book| ref=harv|editor-last=Murdin|editor-first=Paul|year=2001| title = Encyclopedia of Astronomy and Astrophysics | publisher = Institure of Physics Publishing |language = {{ен}} |isbn=978-0-7503-0440-5 |pages=5065}}

* {{Cite book| ref=harv|title=Philip's Astronomy Encyclopedia | publisher=Philip's |year=2002 |isbn=978-0-540-07863-9 | editor-last=Moore|editor-first=Patrick| language = {{ен}} |pages=427}}