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 Asparagus:

This text has been unreferenced on Wikipedia for a very long time. If you can't find a source, be bold and remove it!

"

Subjectively, the first two are the most pungent, while the last two (sulfur-oxidized) give a sweet aroma. A mixture of these compounds form a "reconstituted asparagus urine" odor. This was first investigated in 1891 by Marceli Nencki, who attributed the smell to methanethiol.[10] These compounds originate in the asparagus as asparagusic acid and its derivatives, as these are the only sulfur-containing compounds unique to asparagus. As these are more present in young asparagus, this accords with the observation that the smell is more pronounced after eating young asparagus. The biological mechanism for the production of these compounds is less clear.[citation needed]