{"version":"1.0","type":"rich","provider_name":"EbookNetworking","provider_url":"https://www.ebooknetworking.net","title":"ORIGINAL PATENT APPLICATION NUMBER 720,600 FOR IMPROVEMENTS IN HOLLOW BLADES FOR THE AERODYNAMIC ROTORS OF HELICOPTERS AND WIND MOTORS. (HERTFORDSHIRE AND MIDDLESEX).","author_name":"De Havilland Propellers Limited and Robert John Perdue.","thumbnail_url":"https://www.ebooknetworking.net/books/noimage.jpg","thumbnail_width":330,"thumbnail_height":500,"html":"<a href=\"https://www.ebooknetworking.net/books_detail-B00407TDMU.html\">ORIGINAL PATENT APPLICATION NUMBER 720,600 FOR IMPROVEMENTS IN HOLLOW BLADES FOR THE AERODYNAMIC ROTORS OF HELICOPTERS AND WIND MOTORS. (HERTFORDSHIRE AND MIDDLESEX).</a>","width":400,"height":300}