Template:PlanetMath reference

WARNING : For this template to work, the urlname parameter needs to be used. The id parameter does not work any more (PlanetMath redirects all such links to its main page instead of finding the intended article) due to changes at the "planetmath.org" site during year 2018.

This template survived a merge and deletion proposal earlier during year 2016: Templates_for_discussion/Log/2016_September_20. A similar Template:PlanetMath still works but see the old discussion about objections.