note that teckids 1 sty (but not teckids2style) has CC-BY-SA parts

basically, the handling of the digit 0, but we’re not going to
change anything now; new material should use teckids2style from
the start and, if possible, updated marterial should be converted
(though protocols, presentations, letters, etc. cannot use it yet
as their document classes will have to be written, upon one of them
first being needed)

teckids.sty

@@ -23,6 +23,8 @@
 % of dealing in the work, even if advised of the possibility of such
 % damage or existence of a defect, except proven that it results out
 % of said person's immediate fault when using the work as intended.
+%
+% Note that this style includes teckids1zero under CC-BY-SA 3.0.
 
 \NeedsTeXFormat{LaTeX2e}
 \ProvidesPackage{teckids}