Lastname, Firstname. Facebook post. Month day, year posted. URL
Penguin, Oscar. Facebook post. April 18, 2013. http://facebook.com/openguin/posts/10154065808067067
Lastname, Firstname [or single username]. Twitter post. Month day, year (time posted). URL.
Penguin, Oscar. Twitter post. April 18, 2013 (1:28 PM). http://twitter.com/libechillbro/status/2651151366
Lastname, Firstname [or single username]. "Title of YouTube Video." YouTube video, length of video, Month day, year posted. URL.
Penguin, Oscar. "Root Beer Floats." YouTube video, 0:35, April 18, 2013. http://www.youtube.com/watch?v=4ICGujpcO28
Lastname, Firstname [or single username]. Instagram post. Month day, year posted. URL.
Penguin, Oscar. Instagram post. April 18, 2013. https://instagram.com/p/5pjGjvjTH6/
Username. Tumblr post. Month day, year posted (time posted, if available). URL.
libechillbro. Tumblr post. April 18, 2013 (1:28 PM). http://libechillbro.tumblr.com/post/125058827619/root-beer-floats-are-in-honor-of-national-library-week
Lastname, Firstname [or single username]. "Title of audio track." SoundCloud audio, length of audio track, Month day, year posted. URL.
Penguin, Oscar. "Root Beer Floats." SoundCloud audio, 2:35, April 18, 2013. http://www.soundcloud.com/oscarthepenguin/root-beer-floats