Formatting APS Journal Articles :: Footnotes
Because being the first author on a paper indicates to the scientific community that this individual did the bulk of the experimental work, it is sometimes necessary for the authors to indicate that more than one person is responsible for the experiments. This is indicated by asterisks (*) after the authors' names on the author line of the title page and by a footnote at the bottom of the Title page, above the contact information.
The following form is used to indicate equal contributions:
«fn»*S. Laurel and O. Hardy contributed equally to this work.
Note that the «fn» code has to be typed in before this sentence and that the authors are referred to by only their first initials (with periods) and surnames.