[cc-community] Adding a date to a CC-0 public domain dedication

[Conley Owens]

Hi all,

For books and such, it's customary to have a copyright date, esp. for
purposes of bibliographies, etc.  How would I add a date with a cc-0
dedication?
Would it be self-contradictory to place a copyright line right above a
cc-0 dedication?
E.g.:

""""
Copyright © 2021 by <author>

To the extent possible under law, <author> has waived all copyright and
related or neighboring rights to <title>. This work is published from the
United States.
https://creativecommons.org/publicdomain/zero/1.0/
"""

~cco3