Looking for some WordPress shortcodes to include in php file

I am currently using a neat little plugin from WordPress’ repository called Citationic which displays a little box that generates the correct citation for the individual website to be included in a bibliography. I had a look at the php file and it is quite easy to modify the various templates. However, I am confused how to pull the published date from WordPress.

The APA style is as follows: Organisation. (Publish date). Title. Retrieved Current date, from siteurl.

The php is
$cion_styles = [
“apa” => ‘{sitename}. ({date}). {title}. Retrieved {date}, from {permalink}.’,

Now, my question is to what I have to change the first {date} to display the published date instead of the current date?
I hope that I made myself somewhat clear 🙂

Thanks!