The reference for the dead bee trap Norm Gary designed is A trap to quantitatively recover dead and abnormal honey bees from the hive. J. Econ. Ent. 53:782-785. I used this trap sucessfully in my studies of undertaker bees. The main problems I encountered were that the vaseline which prevents undertakers with corpses from walking out of the trap needed to be reapplied periodically, and that foraging yellow jackets would fly into the trap, cut up the corpses, and carry them away. However, Norm himself no longer uses these traps, and he would be the best person to contact as the pros and cons of different designs. One caution: it is considerably easier to build the Gary trap than some of the other designs. Good trapping.