RT Journal Article SR Electronic T1 Osteopetrorickets: a twin paradox JF BMJ Case Reports FD BMJ Publishing Group Ltd SP bcr0620092012 DO 10.1136/bcr.06.2009.2012 VO 2010 A1 Satvinder Kaur A1 Ketan Kulkarni YR 2010 UL http://casereports.bmj.com/content/2010/bcr.06.2009.2012.abstract AB