RT Journal Article SR Electronic T1 On photographs of the spectrum of nebula in Orion JF American Journal of Science JO Am J Sci FD American Journal of Science SP 339 OP 341 DO 10.2475/ajs.s3-23.137.339 VO s3-23 IS 137 A1 Draper, H. YR 1882 UL http://www.ajsonline.org/content/s3-23/137/339.abstract AB