Williams, J. P.؛ Blitz, L.؛ McKee, C. F. (2000). "The Structure and Evolution of Molecular Clouds: from Clumps to Cores to the IMF". Protostars and Planets IV. ص. 97. arXiv:astro-ph/9902246. Bibcode:2000prpl.conf...97W.
Sandstrom, Karin M.؛ Peek، J. E. G.؛ Bower، Geoffrey C.؛ Bolatto، Alberto D.؛ Plambeck، Richard L. (2007). "A Parallactic Distance of Parsecs to the Orion Nebula Cluster from Very Long Baseline Array Observations". The Astrophysical Journal. ج. 667 ع. 2: 1161. arXiv:0706.2361. Bibcode:2007ApJ...667.1161S. DOI:10.1086/520922.
Wilking, B. A.؛ Gagné, M.؛ Allen, L. E. "Star Formation in the ρ Ophiuchi Molecular Cloud". في Bo Reipurth (المحرر). Handbook of Star Forming Regions, Volume II: The Southern Sky ASP Monograph Publications. arXiv:0811.0005. Bibcode:2008hsf2.book..351W.
Sanders, D. B.؛ Scoville, N. Z.؛ Solomon, P. M. (1 فبراير 1985). "Giant molecular clouds in the Galaxy. II – Characteristics of discrete features". Astrophysical Journal, Part 1. ج. 289: 373–387. Bibcode:1985ApJ...289..373S. DOI:10.1086/162897.
Sandstrom, Karin M.؛ Peek، J. E. G.؛ Bower، Geoffrey C.؛ Bolatto، Alberto D.؛ Plambeck، Richard L. (2007). "A Parallactic Distance of Parsecs to the Orion Nebula Cluster from Very Long Baseline Array Observations". The Astrophysical Journal. ج. 667 ع. 2: 1161. arXiv:0706.2361. Bibcode:2007ApJ...667.1161S. DOI:10.1086/520922.
Dupraz, C.؛ Casoli, F. (4–9 يونيو 1990). "The Fate of the Molecular Gas from Mergers to Ellipticals". Dynamics of Galaxies and Their Molecular Cloud Distributions: Proceedings of the 146th Symposium of the International Astronomical Union. Paris, France: Kluwer Academic Publishers. Bibcode:1991IAUS..146..373D.
Williams, J. P.؛ Blitz, L.؛ McKee, C. F. (2000). "The Structure and Evolution of Molecular Clouds: from Clumps to Cores to the IMF". Protostars and Planets IV. ص. 97. arXiv:astro-ph/9902246. Bibcode:2000prpl.conf...97W.
Sanders, D. B.؛ Scoville, N. Z.؛ Solomon, P. M. (1 فبراير 1985). "Giant molecular clouds in the Galaxy. II – Characteristics of discrete features". Astrophysical Journal, Part 1. ج. 289: 373–387. Bibcode:1985ApJ...289..373S. DOI:10.1086/162897.
Sandstrom, Karin M.؛ Peek، J. E. G.؛ Bower، Geoffrey C.؛ Bolatto، Alberto D.؛ Plambeck، Richard L. (2007). "A Parallactic Distance of Parsecs to the Orion Nebula Cluster from Very Long Baseline Array Observations". The Astrophysical Journal. ج. 667 ع. 2: 1161. arXiv:0706.2361. Bibcode:2007ApJ...667.1161S. DOI:10.1086/520922.
Wilking, B. A.؛ Gagné, M.؛ Allen, L. E. "Star Formation in the ρ Ophiuchi Molecular Cloud". في Bo Reipurth (المحرر). Handbook of Star Forming Regions, Volume II: The Southern Sky ASP Monograph Publications. arXiv:0811.0005. Bibcode:2008hsf2.book..351W.
nasa.gov
O'Dell، C. R. "Nebula". World Book at NASA. World Book, Inc. مؤرشف من الأصل في 2013-07-04. اطلع عليه بتاريخ 2009-05-18.[وصلة مكسورة]