{"version":"1.0","type":"rich","provider_name":"EbookNetworking","provider_url":"https://www.ebooknetworking.net","title":"Introduction to the calculus of variations,  by William Elwood Byerly.","author_name":"Michigan Historical Reprint Series","thumbnail_url":"https://www.ebooknetworking.net/books/141/817/big1418178071.jpg","thumbnail_width":330,"thumbnail_height":500,"html":"<a href=\"https://www.ebooknetworking.net/books_detail-1418178071.html\">Introduction to the calculus of variations,  by William Elwood Byerly.</a>","width":400,"height":300}