Gould, John. A monograph of the Trochilidae, or family of humming-birds, 1861 plates (most signed: J. Gould and H.C. Richter, del. et lith.) v. 1, page vii (author's preface: "To my artist Mr. Richter ... I owe many thanks")
Jackson, Christine E. "H.C. Richter: John Gould's unknown bird artist," in Journal of the Society for the Bibliography of Natural History, v. 9 (1978), pages 10-14 pages 10-11 (H.C. Richter; Henry Constantine Richter, born "about 1821" at Brompton; son of noted historical painter Henry James Richter) page 11 (after sister's death in 1896, he moved to her residence at 56 Frithville Gardens, Hammersmith, from a nearby "home for aged poor"; died 6 years later (16 March 1902, aged 81; listed as "draughtsman" in 1851 census; natural history artist, concentrated on drawing birds in particular)
Jackson, Christine E. Dictionary of bird artists of the world, 1999 page 408 (Richter, Henry Constantine, English bird artist and illustrator who produced drawings on lithographic stones and some watercolors for approximately 1600 plates in John Gould's bird books between 1842 and approximately 1872; born 7 June 1821, Brompton, London; died 16 March 1902, Frithville Gardens, Hammersmith, London; employed by John Gould to paint and lithograph birds after the death of Gould's wife, Elizabeth Gould, in 1841; worked from Gould's designs, drawing on the lithographic stones and supplying background details)
Wikipedia, November 15, 2017 (Henry Constantine Richter (1821-16 March 1902); zoological illustrator who produced numerous lithographs of birds and mammals, mainly under the employment of John Gould)
Wikidata, November 15, 2017 (Henry Constantine Richter (Q1567083); English zoological illustrator)
