How to cite online articles that don't have a publication date? I am very new to the ordeal of incorporating citations into my work, but I'm working on a project for school, and in it, I'm using the APA 6th citation format.
https://www.nationalgeographic.org/encyclopedia/core/
This is a source I used. I believe it falls under the category of &quot;Website&quot; (translated from Norwegian, I'm using a website that shows the different formats of citation for different text types). Now, the link provided is described by NatGeo as an encyclopedic entry, and no authors nor publication date is to be seen anywhere. I couldn't spot it at least. Now, the website I used said that the format of citation for &quot;Websites&quot; is like this:

Blah-blah-blah (National Geographic, 2009)

However, I can't find that date that I need to include at the end. Is there then an altenative format to use? Or am I just not looking properly for said date?
The APA blog answers this:

Determining Website Dates
If no date of publication is provided, use the letters n.d. (which stand for “no date”). The copyright date on the website itself should not be used as the publication date for particular content on that site.

(Note that you should use the updated date if there is one.)
When you have multiple citations for the same website and both have no date, you should append a letter to the end, similar to an actual year: “n.d.-a”, “n.d.-b”, etc.