Roberts, Throp and Co

See also -
- National Museum of American History / Roberts, Throp & Co., Three Rivers, Michigan, United States / https://americanhistory.si.edu/collections/search/object/SILNMAHTL_12961
- Clark, Mason / Roberts, Throp Company Advertisements / http://www.railroadhandcar.com/ ; http://www.railroadhandcar.com/history/catalog/roberts-throp/
- Clark, Mason / Kalamazoo Railroad Velocipede and Car Company Advertisements / http://www.railroadhandcar.com/ ; http://www.railroadhandcar.com/history/catalog/kalamazoo/
- Virginia Tech / Roberts, Throp & Co. - Invincible Thresher / https://imagebase.lib.vt.edu/index.php ; https://imagebase.lib.vt.edu/browse.php?folio_ID=/agriculture/book/robert