> U+0322 RETROFLEX HOOK is an artifact of Unicode.
All characters are artifacts, this one came to Unicode from bibliographic standards,
so that would be where to seek its usage if any.
Joe
RLG COMMENTS ON UNICODE (VERSION DATE: SEPT 11, 1989)
...
c. CEDILLAS AND HOOKS:
Two cedillas and two hooks are required as diacritical marks for bibliographic
transcription, and also for the proper representation of a number of languages
(as documented in ANSI Z39.47-1985 and ISO 5426-1983).
These four diacritical marks are present in the USMARC character set, in ANSEL
(ANSI Z39.47-1985) and in the ISO extension of the Latin alphabet for
bibliographic use (ISO 5426-1983). Their encoding and naming in each of these
character sets is shown in the following table.
USMARC ANSEL ISO USMARC NAME ANSEL NAME ISO NAME
(8-bit) (8-bit) (7-bit)
F0 15/0 5/0 cedilla cedilla cedilla
F8 15/8 5/1 right cedilla right cedilla rude
F7 15/7 5/2 left hook/tail left hook hook to left
F1 15/1 5/3 right hook right hook hook to right
or ogonek
...
