Does anyone know the source for this? I found a Scientific American article and an Amazon listing for an out-of-print book published by Scientific American (per

Does anyone know the source for this? I found a Scientific American article and an Amazon listing for an out-of-print book published by Scientific American (perhaps just a copy of the article). https://www.scientificamerican.com/magazine/sa/1973/03-01/#article-bicycle-technology https://www.scientificamerican.com/magazine/sa/1973/03-01/#a... https://www.amazon.com/Bicycle-technology-S-S-Wilson/dp/B00071F638 https://www.amazon.com/Bicycle-technology-S-S-Wilson/dp/B000... EDIT: The URL includes 'Scientific American March 1973', which matches my first link. EDIT2: So I think that must be the source.