CB – I beg to differ – 2 day Rosh Chodesh is only with a chodesh that is molei (30 days) – so it’s lamed Shevat and Aleph Adar (sorry don’t want to switch between English and Hebrew letters), like yenta said.
It’s for this reason that we don’t process gitten on the first day of a two-day R”Ch. If the date on the get is inaccurate then it doesn’t work and it’s a sofek whether to write lamed shevat or day one of rosh chodesh adar.