Smart Key - Man Pages

If pressed on a cross reference within a man page entry section labeled
NAME, SEE ALSO, or PACKAGES USED, or within a man page C routine
specification (see ‘smart-man-c-routine-ref’) and the man page buffer
has either an attached file or else a man-path local variable
containing its pathname:
  ACTION KEY or ASSIST KEY
     Displays the man page or source code for the cross reference.