Is it possible to refer to a specific section of the supplemental material?

Question

I will soon submit a paper to PRL. In the main text, I refer in many places to the supplemental material, which is divided in 3 parts. Let's say that at page 2 of the main I show a result, and I refer to the 1st section of the supplemental material, at page 3 to the 2nd, and at page 4 to the 3rd.

Should I write in this case something like: "See supplemental material part 1", "See supplemental material part 2", etc or just "See supplemental material" each time, and leaving the reader to figure out where to look?

Answer 1

Supplemental material should generally be organized and referred to just as tightly as the main material: you should think of it as one big document which just happens to be divided into two files.

As such, you should provide explicit, well-localized references to each element you refer to in the supplemental, just like you would in the main text, e.g., "Supplementary Figure 3", "Supplementary Section 6."

Note also that if you adopt this sort of tight "one document" formatting, you are not necessarily using any more words than "See Supplementary Material".

Some examples of articles using this format:

• Stanton, Brynne C., et al. "Genomic mining of prokaryotic repressors for orthogonal logic gates." Nature Chemical Biology 10.2 (2014): 99-105.
• Couzin, Iain D., et al. "Uninformed individuals promote democratic consensus in animal groups." Science 334.6062 (2011): 1578-1580.
• Kiani, Samira, et al. "CRISPR transcriptional repression devices and layered circuits in mammalian cells." Nature Methods 11.7 (2014): 723-726.

Answer 2

It's generally best to avoid making readers figure out anything. I'd write "See supplemental material, part 1" or "See Part 1 of the supplemental material". I can't think of any reason not to, unless perhaps you are extremely close to a page limit.