Zitationen: Anonym 1948: [Jacobson, E. R.] The Lepidopterists' News. The Monthly Newsletter of the Lepidopterists' Society., New Haven 2, S. 79, B15 11158
Huijbregts, H. 1999: [Jacobson, E. R.] Everts, Info, Suppl. 43, S. 45, B15: Sep.
Meijere, J. C. H. de 1946: [Jacobson, E. R.] Entomologische Berichten, Amsterdam 12, B15 10146a, pp. 2-4
Poggi, R.; Conci, C. 1996: [Jacobson, E. R.] Memorie della Società Entomologica Italiana, Genova 75, B15 10160a, pp. 61 (Sammlungsverbleib)
Seehausen, M.; Turiault, M.; Fliedner, H.; Deliry, C. 2023: "A nice old greybeard" - Friedrich Ris' correspondence archived at the Senckenberg Museum Franfurt/Main, Germany. Report/ International Dragonfly Fund. A Journal of the International Dragonfly Fund., Frankfurt 2023 (180), S. 1-84, 12 326, pp. 17-18