For choosing a single article to give to physicians on breastfeeding, I
second Jon's recommendation of the Family Practice Recertification Journal
article, but also nominate:

Cunningham, Allan S., Derrick B. Jelliffe, and E.F. Patrice Jelliffe  1991
  Breast-feeding and health in the 1980s: A global epidemiologic review.
Journal of Pediatrics, 118(5).

My copy comes from La Leche League, Reprint #68, September 1991.  This is an
excellent article on the health benefits to the babies of breastfeeding.

Once "Breastfeeding: Biocultural Perspectives" is published in November, I
would recommend Cunningham's updated version of the above article, which is
a chapter in the book.

----------------------------------------------------------------------------
-------
Katherine A. Dettwyler                                email: [log in to unmask]
Anthropology Department                               phone: (409) 845-5256
Texas A&M University                                    fax: (409) 845-4070
College Station, TX  77843-4352