http://www.slideshare.net/moriwaka/red-hat-software-collections http://blog.co-mit.com/post/15/RedHat+Software+Collections%E3%81%AF%E7%B4%A0%E6%99%B4%E3%82%89%E3%81%97%E3%81%84 http://www.idcf.jp/blog/cloud/software-collections-for-centos-…