HP 82153A Owner's Manual page 68

PRAXIS REGPLOT
STKPLOT
PRFLAGS PRSTK
PRKEYS PRΣ
PRPLOT ACX
PRPLOTP ACA
PRX
PRA
ACCHR
SKPCHR
PRREG PRP
PRREGX LIST
ACCOL ACSPEC
SKPCOL BLDSPEC
PRBUF