Barry T Hirsch 
Labor Unions and the Economic Performance of Firms [PDF ebook] 

Hirsch develops a model of union rent-seeking in which the unions capture a share of quasi-rents that make up the normal ROI in long-lived capital and R&D. He finds that in response, firms adjust their investments in vulnerable tangible and intangible capital. Hirsch also attempts to explain the connection between the contraction of the size of unions which occurred in the 1970s and firms’ lower profitability, diminished market value, and lower investment levels.