The following URLs are provided to access online resources related to ProbOnto
Other collections of distributions and/or their relationships
Leemis chart - eighty univariate distributions and an excellent reference resource for relationships, their derivations etc. About 40 relationships in ProbOnto are based on this reference collection.
Distributome - database with nearly hundred univariate distributions, their properties and relationships.
UncertML - reference resource for selected uni- und multi-variate distributions.
UUPDE - collection of ~500 univariate probability distributions with up to 60 properties per distribution.
John Cook collection - selected relationships for univariate distributions.
Wikipedia - Relationships among probability distributions.
Protégé is a free, open-source ontology editor. Download it from the project website - http://protege.stanford.edu/