When citing maps that are part of another source (for example maps used as illustrations in a journal article or book), see the instructions under Images and figures.
(Organization/Cartographer's Last name, Year)
Organization/Cartographer's Last name, First name and Last name, First name (Year). Title, Scale. X. ed. Place of publication: Publisher. URL [Accessed: date].
There are many different map services online where you create your own map images or retrieve geodata from dynamic maps. Below is an example of how you can cite such map services.
Keep in mind that if you want to include a map in your assignment you must first check the copyright terms of the material you are using!
Map X. Title, scale x:xxxxxx (Organization, Year). Copyright information.
If you don't want to include a map, only reference it, you can write the in-text citation in the following format.
(Organization, Year)
Organization/Publisher (Year). Title, Scale. Name of the map service/platform. URL to map image [Accessed: date].