Citation Hunt

The Wikipedia snippet below is not backed by a reliable source. Can you find one?

Click I got this! to go to Wikipedia and fix the snippet, or Next! to see another one. Good luck!

In page Periodic acid–Schiff stain:

"

If the PAS stain will be performed on tissue, the recommended fixative is 10% neutral-buffered formalin or Bouin solution. For blood smears, the recommended fixative is methanol. Glutaraldehyde is not recommended because free aldehyde groups may be available to react with the Schiff reagent, which may result in false positive staining.[5]