I have posted Estate and Gift Tax Problems of Principals and Agents Under Durable Powers of Attorney, 66 Tax Notes 1009 (1995), on SSRN.  Here is the abstract:

The combination of advances in life expectancies and improvements in medical technologies has made it increasingly important to plan for a client's possible future incapacity. As a result, the use of durable powers of attorney has exploded in recent years. Indeed, estate planners now typically include such powers and living wills as components of a client's estate plan along with traditional wills and trusts. However, the use of durable powers of attorney can create serious estate and gift tax problems for both the principal and the agent. This article discusses these tax problems in light of several recent cases and rulings, and suggests drafting strategies to address these tax concerns.