1. Medicare Provider Analysis and Review (MEDPAR) File,1988
2. Plymouth Meeting;IMS America, Ltd.,1992
3. Industry strategies;Cowen & Company,1992
4. Quality of life in patients with rate response pacemakers: a randomized cross-over study;Oto;PACE,1991
5. A randomized comparison of quality of life and exercise capacity with DDD and VVIR modes;Bubien;PACE,1990