(en) « Jackson, Horatio Nelson », dans John J. Duffy, Samuel B. Hand, Ralph H. Orth, The Vermont Encyclopedia, Hanover, University Press of New England, (ISBN9781584650867, lire en ligne), p. 169
jstor.org
(en) Peter J. Hugill, « Good Roads and the Automobile in the United States : 1880-1929 », Geographical Review, vol. 72, no 3, , p. 328 (lire en ligne, consulté le )
legion.org
centennial.legion.org
(en) « Horatio Nelson Jackson Organizer for Vermont American Legion », sur The American Legion Centennial Celebration, (consulté le ) : « H. Nelson Jackson: A friend of President Theodore Roosevelt and often vacationed in his New York summer home. WWI was looming and Dr Jackson requested enterance into the Military. He was denied, at first due to his age. However, Roosevelt made it happen and Horatio Nelson Jackson became a Medical officer. »
militarytimes.com
valor.militarytimes.com
(en) « Horatio N. Jackson », sur Hall of Valor, Sightline Media Group (consulté le )
minneapolisfed.org
Chiffres de l'inflation aux États-Unis basé sur les données de la Federal Reserve Bank of MinneapolisConsumer Price Index (Estimate) 1800-. Dernière visite le 16 mai 2020.
newspapers.com
(en-US) « Bertha R W Jackson marries Kolk », The Burlington Free Press, Burlington (Vermont), , p. 8 (lire en ligne, consulté le )
(en) « Former Editor Dies at Age 77 », Burlington Free Press, Burlington (Vermont), , p. 16 (lire en ligne)
(en) « Persons from Many Parts of Vt. to Attend Col. Jackson's Funeral », Burlington Free Press, (lire en ligne)
(en) « Col. Jackson, Legion's Father in Vt., Is Dead », Burlington Free Press, (lire en ligne)