Mizar Language
mizar.uwb.edu.plIs there an example of an "article"?
There are "1498 articles written by 278 authors and 73460 theorems, 14291 definitions" at http://mmlquery.mizar.org/
I tried to pick an easy one: "x=y => x*z=y*z":
http://mmlquery.mizar.org/mmlquery/fillin.php?entry=SURREALR...
Why it says "sureal"?
It's about surreal numbers https://en.wikipedia.org/wiki/Surreal_number