RT Journal Article SR Electronic T1 On triple objectives with complete color correction JF American Journal of Science JO Am J Sci FD American Journal of Science SP 429 OP 435 DO 10.2475/ajs.s3-18.108.429 VO s3-18 IS 108 A1 Hastings, C. S. YR 1879 UL http://www.ajsonline.org/content/s3-18/108/429.abstract AB