I'm not aware of any use of -:-.
Even though it's not "citeable", the easy way out is to look at the German page of Wikipedia on "Division", which shows the ":" notation. It also shows the -:- notation as an alternative and attributes both to Leibnitz.
In reply to Re^8: OSCON Perl Unicode Slides
by Corion
in thread OSCON Perl Unicode Slides
by tchrist
| For: | Use: | ||
| & | & | ||
| < | < | ||
| > | > | ||
| [ | [ | ||
| ] | ] |