Weinberger, R., & Acker, A. Planetary Nebulae: Proceedings of the 155th Symposium of the International Astronomical Union, Held in Innsbruck, Austria, July 13-17, 1992. Springer International Publishing.
Chicago-referens (17:e uppl.)Weinberger, Ronald, och Agnès Acker. Planetary Nebulae: Proceedings of the 155th Symposium of the International Astronomical Union, Held in Innsbruck, Austria, July 13-17, 1992. Cham: Springer International Publishing.
MLA-referens (8:e uppl.)Weinberger, Ronald, och Agnès Acker. Planetary Nebulae: Proceedings of the 155th Symposium of the International Astronomical Union, Held in Innsbruck, Austria, July 13-17, 1992. Springer International Publishing.
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