http://chessok.com/shop/index.php?main_page=product_info&cPath=7_72&products_id=716&zenid=32m0min8mtkfvj040m7d42r045
https://www.amazon.com/How-Reassess-Your-Chess-Imbalances/dp/1890085138/ref=sr_1_1?ie=UTF8&qid=1495331313&sr=8-1&keywords=jeremy+silman+reassess+your+chess
https://www.amazon.com/Play-Winning-Chess-Yasser-Seirawan-ebook/dp/B009E3HDAY/ref=sr_1_1?ie=UTF8&qid=1495331361&sr=8-1&keywords=yasser+seirawan
https://www.amazon.com/Winning-Chess-Strategies-ebook/dp/B004Y6AI30/ref=pd_sim_351_2?_encoding=UTF8&psc=1&refRID=1NA64X6GRXE53QK6C1PY
https://www.amazon.com/Winning-Chess-Openings-Yasser-Seirawan-ebook/dp/B007CK6UFK/ref=pd_sim_351_3?_encoding=UTF8&psc=1&refRID=FAJEGEB9ENECDPX78CYW
And Play, analyze, maybe Fritz and use the engine to see where you went wrong each game, after you've looked at it yourself. That will do it.
a lot of people get stuck at 900 like me and I need some tips others may as well