I have submitted a manuscript to Journal of Membrane Science a month ago.Now I would like to submit another one to the same jounal. I wish to cite the former manuscript that is still under reviewing process. Can I do so? If yes, what should I do?
Generally, this is not acceptable. Citations are made when the reference to be cited has at least DOI or volume and page numbers. In the past it was allowed to cite a paper when it is in press, But nowadays good journals do not accept citations of papers under review, in preparation and in press (without DOI number).