A 21 micron emission feature in four proto-planetary nebulae

MLA

Bruce J. Hrivnak, et al. “A 21 Micron Emission Feature in Four Proto-Planetary Nebulae.” The Astrophysical Journal, vol. 345, Oct. 1989, p. L51. EBSCOhost, https://doi.org/10.1086/185550.

APA

Bruce J. Hrivnak, Sun Kwok, & Kevin Volk. (1989). A 21 micron emission feature in four proto-planetary nebulae. The Astrophysical Journal, 345, L51. https://doi.org/10.1086/185550

Chicago

Bruce J. Hrivnak, Sun Kwok, and Kevin Volk. 1989. “A 21 Micron Emission Feature in Four Proto-Planetary Nebulae.” The Astrophysical Journal 345 (October): L51. doi:10.1086/185550.