Special forms for Supplementary Recommendations?

<p>Should supplement rec. letters be written with a special form? or is a generic letter written on Word/plain paper fine? I don't even think there are special forms for supplement recs.</p>

<p>Thanks for the help :)</p>

<p>Also, not to jack the topic, but a related question: When do supplementary recs need to be submitted by? Jan. 1?</p>

<p>I asked my Rutgers research mentor to send a supplemental rec using the university's letterhead.</p>