yarn add fails with most recent version

[davidgs]

Trying to install using yarn fails:

address-test % yarn add ubilabs/google-maps-react-hooks
yarn add v1.22.19
[1/4] 🔍  Resolving packages...
error Can't add "@ubilabs/google-maps-react-hooks-library-and-examples": invalid package version undefined.
info Visit https://yarnpkg.com/en/docs/cli/add for documentation about this command.

yarn add @ubilabs/[email protected] succeeds.