Event-B Mathematical Language
There are two versions of the mathematical language.
The latest version (V2) has been supported by the Rodin platform since release 1.0.0 and is available in PDF format.
The original version (also available in PDF format) was used by the Rodin platform up to releases 0.9.x.
The changes between these two versions are summarized in Changes_to_the_Mathematical_Language_of_Event-B.
Proposals for changes to the mathematical language specification are collected here.