Kenneth K. Landes (1951, 1966): A Scrutiny of the Abstract, I & II.
Paul D. Lowman (1988): The Abstract Rescrutinized.
The Royal Society (1966): Guide for Preparation and Publication of Abstracts.
All online in: http://www.geo.utexas.edu/faculty/marrett/AdvStructure/Abstracts.pdf
UPDATE: Unfortunately the University of Sidney changed its policy. You need an account to log in.
University of Sidney, Generic Skills → Communication Skills → Scientific Writing Notes:
https://sydney.edu.au/science/biology/learning/generic_skills/scientific_writing.shtml
There you find a link to the Scientic Writing Notes of the University of Sidney:
“Brief notes on writing a practical report, an essay and a literature review
are given in the Scientific Writing (pdf) notes and in specific sections of the manual.”