Clarified meaning of "ISO 9660:1999" as Enhanced Volume Descriptor of ECMA-119 4th Edition

xorriso/xorrisofs.texi

@@ -50,7 +50,7 @@
 @c man .\" First parameter, NAME, should be all caps
 @c man .\" Second parameter, SECTION, should be 1-8, maybe w/ subsection
 @c man .\" other parameters are allowed: see man(7), man(1)
-@c man .TH XORRISOFS 1 "Version 1.5.7, Sep 05, 2024"
+@c man .TH XORRISOFS 1 "Version 1.5.7, Oct 06, 2024"
 @c man .\" Please adjust this date whenever revising the manpage.
 @c man .\"
 @c man .\" Some roff macros, for reference:
@@ -162,8 +162,11 @@ Production of this directory tree may be enabled by option -J.
 @*
 @cindex ISO 9660:1999, _definition
 @strong{ISO 9660:1999}
-is the name of an additional directory tree which provides longer
-filenames. It allows single file names to have up to 207 characters.
+is the folkloric name of an additional directory tree which provides longer
+filenames. It allows single file names to have up to 207 characters. Its
+starting point is specified officially as Enhanced Volume Descriptor in
+ECMA-119 4th Edition.
+@*
 It might be of use with some older computer system boot
 facilities which read neither Rock Ridge nor Joliet but
 need longer filenames nevertheless.
@@ -714,8 +717,8 @@ and file size of up to 400 GiB - 200 KiB. (This size limitation is
 set by the xorriso implementation and not by ISO 9660 which would
 allow nearly 8 TiB.)
 @*
-Pseudo-level 4 enables production of an additional ISO 9660:1999
-directory tree.
+Pseudo-level 4 enables production of an additional directory tree beginning at
+an Enhanced Volume Descriptor (aka ISO 9660:1999) as of ECMA-119 4th Edition.
 @c man .TP
 @item -disallow_dir_id_ext
 @kindex -disallow_dir_id_ext   enforce ISO level 1 directory names