Foundational UML
Alf zone
Alf - the Action Language for Foundation UML - is a UML-friendly textual "surface language" intended for use together with fUML. Useful for those tasks in Activity and StateMachine diagrams that don't lend themselves to graphical modelling.
fUML zone
Semantics of a Foundational Subset for Executable UML Models (fUML®)
A subset of Unified Modeling Language (UML®) with semantics for execution and an extended event and notification model.