Hi!
There are no special prefixes for them, but the standard workaround is to:
1. Execute a "set user variable" in the market, e.g. "Home Team +1" with the
scope "individually for each sports evet". Set that variable to whatever you need to know about that market, e.g. "market_volume" or "r_1_back_price". If you need to constantly monitor this parameter, set the trigger to be executed "no more often than X sec" where X is the market refresh rate.
2. In the other market where you need to use that information, just use the variable name, as it will be visible in all markets within that event.
