awk '
BEGIN{
	print ".nr Rp 1"	# supress ... Rx lines
	first=1
}

#these come first
$1=="..." && $2=="Rx"{
	ref[$4] = $3
	next
}

first {
	printf(".lf %d %s\n", 1, inputfile)
	lineoffset=NR-1
	first=0
}

$1==".Rf"{
	if($2 in ref)
		$2=ref[$2]
	else
		printf("tref: %s:%d: no ref for %s\n",
			inputfile, NR-lineoffset, $2) >"/dev/stderr"
}

{
	print
}

' $*