Here are four different, but equally correct, ways to attribute this photo to its creator:
Matt Morse's "Untitled." (Photo).
Untitled by Matt Morse.
"Untitled." By Matt Morse (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons. Available at http://commons.wikimedia.org/wiki/File:Michigan_City_Lighthouse.jpg
When possible, provide a credit list of material you used that adheres to best practices. Doing so allows not only your material, but the materials you attribute, to be found by search engines and other web discovery tools. Make the Author, Source, and License into links the user can follow.
You can also mention the source in the credits within the media itself. Crediting videos can be a simple list of the materials used with their associated licenses in a screen at the end of a video. For audio, it can be a verbal recitation of credits at the end of the recording.
When citing sources online, it is best to link to those sources directly whenever possible. For an in-text citation, use a superscript number in brackets that matches a footnote at the bottom of the page showing the full citation. Then make sure that the link in your citation is a hyperlink to the original source. For example:
The Creative Commons license is the most widely used licensing framework internationally used for OER.
Full citation in footnote:
20. Miao, Fengchun, et al. Open Educational Resources: Policy, Costs, Transformation. E-book, UNESDOC, 2016. unesdoc.unesco.org/ark:/48223/pf0000244365. Accessed 23 Jan. 2020.
For more examples of how in-text citations should look, see Wikipedia: https://en.wikipedia.org/wiki/Motion_graphics
For more information on how to cite sources, see the Citation Styles box.