Adding an output title to each page

A title and subtitle can be placed on each and every page using

For example in the Model library file co2mge.gms at various points the following appear

$TITLE  Carbon-Related Trade Model (static)  (CO2MGE,SEQ=142)

$stitle: CARBON-RELATED TRADE MODEL - BENCHMARK REPLICATION

$stitle:CARBON-RELATED TRADE MODEL - OECD ABATEMENT WITH HIGH LEAKAGE

which results in every page of the LST file being started with the line

Carbon-Related Trade Model (static)  (CO2MGE,SEQ=142)

and pages after the $stitle having pages that start with

Carbon-Related Trade Model (static)  (CO2MGE,SEQ=142)

: CARBON-RELATED TRADE MODEL - BENCHMARK REPLICATION

until the next stitle where the page heading becomes

Carbon-Related Trade Model (static)  (CO2MGE,SEQ=142)

:CARBON-RELATED TRADE MODEL - OECD ABATEMENT WITH HIGH LEAKAGE