1. Boardman C, Sundquist E (2009) Toward understanding work motivation. Am Rev Public Adm 39(5):519–535
2. Government Accountability Office (2015) Federal workforce: improved supervision and better use of probationary periods are needed to address substandard employee performance. Report to chairman, committee on Homeland Security and Government Affairs US Senate. Government Accountability Office, Washington, DC
3. Merit Systems Protection Board (2016) U.S. Merit systems protection board. http://www.mspb.gov/index.htm. Accessed 28 Mar 2016
4. Stillman R (2010) Public administration concepts and cases. Wadsworth, Boston
5. U.S. Government (2005) Code of federal regulations. U.S. Government Publishing Office. https://www.gpo.gov/fdsys/pkg/CFR-2005-title5-vol1/xml/CFR-2005-title5-vol1-sec315-201.xml. Accessed 2 Feb 2016