{"version":"1.0","type":"rich","provider_name":"EbookNetworking","provider_url":"https://www.ebooknetworking.net","title":"Anthracite mechanical-mining investigations: Use of yielding steel supports (props) in combination with backfilling for mining thick, flat beds","author_name":"John C. Hartley","thumbnail_url":"https://www.ebooknetworking.net/books/B00/3HK/bigB003HKQUFE.jpg","thumbnail_width":330,"thumbnail_height":500,"html":"<a href=\"https://www.ebooknetworking.net/books_detail-B003HKQUFE.html\">Anthracite mechanical-mining investigations: Use of yielding steel supports (props) in combination with backfilling for mining thick, flat beds</a>","width":400,"height":300}