Because Google removed all G+ author information from search, this tool is no longer available..
Use the Google+ Author checker to find the author of a specific web page. Submit multiple URLs and this tool will check the HTML markup / structured data containing Google Plus authorship information.
The syntax used for G+ Authorship:
After performing the check the Google PLus author name and Google Plus profile URL are returned, when found, for each URL. You can submit a maximum of 10 URLs and export the results to .cv.