@book{18710, author = {Van Laar, M.W. and Van Ooyen-Houben, M.M.J.}, title = {Nationale drugmonitor : jaarbericht 2016 [PDF]}, publisher = {Trimbos-instituut}, year = {2016}, address = {Utrecht}, url = {http://www.google.com/search?q=nationale-drugmonitor jaarbericht-2016} }