\doabstract{Writing and checking complete proofs in {\LaTeX}}
{Bob Neveln and Bob Alps}
{ProofCheck is a system for writing and checking mathematical
proofs. Theorems and proofs are contained in a plain {\TeX} or {\LaTeX}
document. Parsing and proof checking are accomplished through Python
programs which read the source file. A general explanation of the use
and structure of the system and programs is provided and a sample proof
is shown in detail. The work done by the authors has been based on
standard sentence logic, a non-standard predicate logic and set theory
with proper classes.  Theorems and proofs based on other foundations may
be checked if external data files are modified.  Four such data files
and their possible modifications are described. In addition, the extent
to which the formal language can be shaped to accommodate an author's
preferences is discussed.}