If you are using dynamic views, you can also use extended naming to see the set of labels applied to versions of the element:
% ls myfile.c@@
Note that the output also includes the 'main' branch. You can omit the branch(es) on a non-directory element simply:
% ls -1F myfile.c@@ | grep -v /
Extra credit - You can also use extended names to see the set of labels applied to versions of a particular branch:
% ls -1F myfile.c@@/main/mybranch | grep -v / | grep '[A-Za-z]'
(the trailing 'grep' assumes labels have at least one alphabetic character and will omit version numbers that would otherwise also be included in the output.) That output will also include 'LATEST' but you can easily omit that, too, if desired.