1.http://www.tech-coffee.net/sccm-2012-r2-environment-preparation-requirements/sql
2.http://www.scconfigmgr.com/2013/12/18/configmgr-2012-r2-prerequisites-installation-tool/ide
3.http://prajwaldesai.com/installing-sql-server-2012-for-configuration-manager-2012-r2/ui
4.Configuration Manager 2012 – Troubleshooting Log Filesspa