Ljunggren, B. (1966). The Uppsala spectral classification and the interstellar absorption in a region near the north galactic pole. [s.n.].
Chicago Style (17th ed.) CitationLjunggren, Bertil. The Uppsala Spectral Classification and the Interstellar Absorption in a Region Near the North Galactic Pole. Uppsala: [s.n.], 1966.
MLA (9th ed.) CitationLjunggren, Bertil. The Uppsala Spectral Classification and the Interstellar Absorption in a Region Near the North Galactic Pole. [s.n.], 1966.
Warning: These citations may not always be 100% accurate.
