Applicants at MathJobs.Org enter reference writer names into the system and may, at any time, have email sent to the reference writer giving login and password information.
Please note that Mathjobs.Org expects your login to be your email address as entered by the applicant. In the email, you (as a reference letter writer) will be given a choice to either link directly to the letter upload screen, or login using the exact email identity supplied by the applicant and the password contained in the email.
If you log in and do not see all the applicants on your REFS list, it is due to multiple email addresses being used by applicants to list you in the system. In that case, please clarify with the applicants the one address to use; an applicant can change the coversheet at any time.