https://www.theatlantic.com/technology/archive/2023/02/leland-stanford-california-stock-farm-silicon-valley-tech/672979/

https://www.theguardian.com/books/2023/may/10/palo-alto-book-malcom-harris-interview

https://harnessmuseum.com/content/charles-marvin

https://storymaps.arcgis.com/stories/3c3df5817a7245868a350875ca15212f

Charles Marvin: Training the Trotting Horse - digitoitu opas (kaksi eri lähdettä)

http://www.survivorlibrary.com/library/training_the_trotting_horse_1890.pdf

https://www.biodiversitylibrary.org/item/90207#page/7/mode/1up