For a background material see Debian bug #1036826 or the home page of "Bug Reports" in Debian for the package "po4a".
For a three font case, add a temporary roman font change in an argument, that will say (including italic corrections) "\/\fR" in front of the roman (upright) part and "\,\fP" after it. An example from "groff_man.7" .IR topic [\c .BI , " another-topic"\c .RB "].\|.\|.\& \e\- "\c .I summary-description (N.B. 'RB' is used for a pure roman font as an 'R' font macro does not exist) translates to .IB topic\/\fR[\,\fP ", " "another-topic\/\fR].\|.\|.\& \e\- \,\fPsummary-description" or use '\' to break a long line into two physical lines (one logical line) .IB topic\/\fR[\,\fP ", " "another-topic\/\fR].\|.\|.\& \e\- \ \,\fPsummary-description" The readability for humans suffers with such a change.
