Article history: Received 23 February 2010 Revised 12 August 2010 Accepted 18 September 2010 Available online xxxx Communicated by Matthias Beck

Article history: Received 5 February 2010 Received in revised form 21 September 2010 Accepted 21 September 2010 Available online 18 October 2010 Editor: T.M. Harrison

Article history: Received 25 July 2013 Received in revised form 9 November 2013 Accepted 18 January 2014 Available online 4 February 2014

Article history: Received 12 February 2008 Received in revised form 16 June 2008 Accepted 18 June 2008 Available online 26 June 2008

Article history: Received 21 February 2011 Received in revised form 18 May 2011 Accepted 12 June 2011 Available online 22 June 2011

Article history: Received 18 February 2014 Received in revised form 17 December 2014 Accepted 30 December 2014 Available online 10 January 2015

Article history: Received 18 February 2009 Received in revised form 4 August 2009 Accepted 1 September 2009 Available online 6 September 2009

To submit your answers to this test and earn 3 hours of CE credit, go www.aaoinfo.org log in as a member. Select the Education tab, then AJO-DO Tests. Purchase current test, or for any issue published preceding 12 months. The fee each is $20. You will take online but can download print PDF version test. Results are tabulated immediately. you must answer 75% questions correctly. If do not receiv...

Article history: Theoretical models which a Received 18 July 2008 Received in revised form 8 December 2008 Accepted 6 February 2009 Available online xxxx