Delegating in the Workplace, available at http://www.adb.org/publications/delegating-workplace, argues that the act of delegating calls for and rests on trust. In organizations, delegation had better be understood as a web of tacit governance arrangements across quasi-boundaries rather than the execution of tasks with definable boundaries. The article covers contract law, oral contracts, and psychological contracts but supports also more recent calls for moral contracts, given the gradual erosion of corporate career structures in the last 20 years.
Trust and Breach of the Psychological Contract. http://www.jstor.org/stable/2393868?seq=2#page_scan_tab_contents
Hao Zhao, Sandy J Wayne, Brian C Glibkowski and Jesus Bravo (2007) The impact of psychological contract breach on work-related outcomes: A meta analysis. Personnel Psychology. 60 (3), 647–680.
Consequences of the psychological contract for the employment relationship: a large scale survey. http://eprints.lse.ac.uk/829/
Psychological contract breach and job attitudes: A meta-analysis of age as a moderator. http://www.sciencedirect.com/science/article/pii/S0001879107001091
A suggestion to add to the other answers: Try an indirect approach, that is, instead of looking directly for the concept that it's interesting for you, think about situations that usually provoke that contract breach, for instance, downsizing.
Once there, you are going to find many articles dealing with the subject you are interested in.
Though not direct, we draw on psychological contract theory to explain how negative employee performance outcomes can arise under long-term employment contracts where they are perceived to be breached or violated. All the best, Andrew