@TechReport{economics.dp.2009-28,
 author = {Clark, Derek J. and Sand, Jan Yngve},
 title = {Endogenous Technology Sharing in R&D Intensive Industries},
 type = {Economics Discussion Paper},
 institution = {Kiel Institute for the World Economy},
 year = {2009},
 number = {2009-28},
 url = {http://www.economics-ejournal.org/economics/discussionpapers/2009-28}
}