Molecular Plant Pathology Online
How to cite an article published in MPPOL
A citation of an article published in MPPOL should give the authors' names, the title of the article and the name of the journal (as for a printed journal), then, instead of volume and page numbers, the internet address, like this:
Ballance GM, Lamari L, Kowatsch R, Bernier CC, 1996. Cloning, expression and occurrence of the gene encoding the ptr necrosis toxin from Pyrenophora tritici-repentis. Molecular Plant Pathology On-Line, http://www.bspp.org.uk/mppol/1996/1209ballance
The latter part of the address, ...1996/1209ballance, indicates the date of publication by year (1996), month (12) and day (09), and the name of the first author (ballance).
You should, of course, consult your publisher's "instructions to authors" for the precise format of citations of electronic publications.