Penguin Statistics highly welcome any form of API usage but we would like to kindly ask you to obey our data license Attribution-NonCommercial 4.0 International (CC BY-NC 4.0). Although we generally do not provide any form of rate limit (Advanced Query resource, in Penguin Statistics Backend, is the only exception), we still want to ask you to fairly use the service ;)
You could contact us using various methods including:
The support chat window at the bottom right corner located at the homepage of Penguin Statistics.
E-mail to the webmaster
alvissreimu [at] gmail.com