Reference Letter Exceptsより引用（一部改変）。
MGHのfaculty用のセミナー"Drafting Your Chief's Letter"の資料です。
facultyの昇進のための推薦状なので量や内容はちょっと大目ですが、書き出しなどの言い回しは参考になりますね。
またHarvard Medical Schoolのサイト Administrator Resources/Appointments and Promotions/Forms, Guidelines and Tools の資料も参考になるかもしれない。
追記：こういう本もよさそうですね。
Instant Recommendation Letter Kitのページ紹介
追記
http://gsi.berkeley.edu/media/sample-recommendation-letter.pdf
や以下にあげるような
https://www.med.illinois.edu/facultydev/letterofref/stronglettersample.phpもよさそうなサイトです。
Letters of Reference
Letter Sample
Information about writing the letter
STRONG Letter of Recommendation for a Good Student
Source: University of Washington, Family Medicine Residency Selection & Career Advising http://www.fammed.washington.edu/predoctoral/advising/LORgood.html(多分リンク切れ)
July 12, 2000
Dear Residency Program Director:
I am pleased to write a letter of recommendation for Margaret Beaufort who is applying to your family medicine residency program. Margaret participated in our 4-week maternal and child health elective program in the Department of Family Medicine.
During the MCH elective Margaret worked closely with the MCH team which consists of the resident staff, maternal and child health fellows, attendings in family medicine, pediatrics, and obstetrics and gynecology. The MCH team cares for over 700 mothers and infants per year. During this elective she worked in the outpatient setting in a consortium of community health centers serving mostly underserved women and children from a variety of cultural backgrounds. In the inpatient setting Margaret worked with the team in caring for the needs of laboring women and continued to care for them on the postpartum floor and cared for their babies in the Nursery. Margaret was a very motivated and hard working student and by the end of the rotation was serving in the first year resident role. She worked extremely well with the residents and fellows and was well accepted by the nursing staff. She was a conscientious student and showed an excellent fund of knowledge and a willingness to go beyond the usual role of students, demonstrating a commitment to continuity in caring for her patients. Margaret also participated in our MCH fellowship seminar series where we attempt to introduce policy level issues focusing on the broader issues facing the delivery of MCH care.
In summary, I highly recommend Margaret Beaufort for residency training in family medicine. I think she will be an outstanding resident and will positively contribute to whatever residency program is able to recruit her.
Sincerely,
Richard D. York, M.D.
This letter received a high rating because the writer knew the student well and was able to give specific examples and clinically relevant information.
（https://www.med.illinois.edu/facultydev/letterofref/stronglettersample.phpより引用）