“The Splendid Source” was seen by 7.59 million viewers

Stewie, Brian and Meg are seen in this episode but very briefly (and very small) waving goodbye to Peter and Lois in the original broadcast of this episode.

They are seen in the deleted scenes and an extra scene at the end of the DVD version.

The lead singer from Asia (1981–1986)(1989–Present), John Payne is featured in this episode requesting Family Guy play one of their songs.

The song that plays is ‘Only Time Will Tell’. Payne actually replaced the original lead singer John Wetton & it's worth mentioning that Wetton is actually the lead vocalist for the song ‘Only Time Will Tell’, not Payne.

The broadcast version of this episode ends with the credits rolling after ‘Monkey Scratch’, but on the DVD, after the monkey, it cuts back to the house with that family sitting in the living room discussing Peter's trip and Brian, Meg & Chris want to hear the joke.
Peter tells the joke & after the punch line, ‘your vagina's in the sink’, he leaves because he has pooped himself again.

Deleted Scene from the Volume 9 DVD:

When Lois is holding the map of Maine and is telling Peter about the cabins she says she can't remember the last time they went away for the weekend.

Peter: What do you mean, we went to that Asian magic show.
(Cut to a theater with a magician on stage with an all Asian crowd)
Magician: Now as you can clearly see, I have a pen. Now watch it disappear.
(The magician simply turns the pen vertically and the crowd Ooooo's)
Magician: And now.
(The magician turns the pen horizontally)
Man in Crowd: Ooh he bring it back!

Deleted Scene from the Volume 9 DVD:

(Peter enters the living room and sits on the couch)(His phone buzzes)
Peter: Who's texting me?
(Peter laughs and poops himself & Joe and Glen are heard off screen laughing)
Peter: Damn it! Stop it you guys, you're ruining all my clothes!
(Brian enters from the kitchen and sniffs the air)
Brian: Peter can I roll in that to hide my scent from my enemies?

Deleted Scene from the Volume 9 DVD:

Lois: Now remember kids, Brian is in charge while we're gone. I want you all to listen to him.
Chris: Listen means here
Stewie: If you don't pay enough attention to me, I'm going to put ketchup on my face & pretend I jumped off the roof.
Lois: Oh and Chris, if Meg kills herself this weekend, don't tell us until we get home. Your father and I need this time. Okay, love you kids.
Alright grown ups! We are all gonna get laid!

Deleted Scene from the Volume 9 DVD:

Peter: And when we find the source, we will have made one of the great breakthroughs in history. Like the invention of rape.
(Cut to the interior of a cave with a prehistoric couple)
Caveman: Would you like to have sex with me?
Cavewoman: No (and walks off screen)
Caveman: Oh darn. (after thinking about it) Unless...

Deleted Scene from the Volume 9 DVD:

(After the guys get beaten in the parking garage)
Glen: Fellas, although this isn't required of me, it would be ethically improper not to advice you avoid all contact with my blood or bodily fluids, especially if you have any small cuts on your hands or open sores.
Man: Yeow! Thanks.
Glen: Hey, we're all in this together.

Deleted Scene from the Volume 9 DVD:

(On Joke Island, the dean leads Peter, Joe, Glen & Cleveland into the cafeteria)
Dean: Would you gentleman care for something to drink? Maybe a little snack?
Peter: Yeah that'd be nice.
Glen: Sounds good.
Dean: Alright, we have milk, milk, lemonade, Oh and around the corner fudge is made.
Peter: (elbows Glen) Boobs, Pee and Poop. That's what he's talking 'bout.

Deleted Scene from the Volume 9 DVD:

(Escaping from the cell)
Peter: Come on let's get outta here.
Cleveland: I'm wounded ya bastard!
Peter: Oh come on, you're fine, you guys get shot all the time. Alright let's go!

Animation Error:

In the scene in Glen's bedroom, we see Quagmire has a mirrored ceiling.

The abstract art on Glen's wall has a red triangle in it but in the reflection, the triangle is missing

Animation Error:

The dirtiest joke ever written is apparently simply “Guess What, Chicken Butt”, but the card clearly has more written on it.

Animation Error:

The moon is full when guys are marched to the entrance of the temple but it's a crescent moon when they are in their cell.
(Unless we're supposed to assume they were in the cell for days but there's no indication in the episode of any great amount of time passing)

This episode is adapted from and named after the 1956 Richard Matheson (02/20/1926-) short story, ‘The Splendid Source’

Quagmire falls asleep and meets up with movie character ‘Freddy Krueger’ from the ‘Nightmare on Elm Street’ series.

Peter's line, if you poop in your dreams you poop for real, is a nod to the movies as well, since the concept of the movies was Freddy would stalk and kill teenagers in their dreams and when he did, they would die in the real world.

During the telling of the journey of the dirty joke, the character ‘Bender’ appears from Matt Groening's ‘Futurama’ (1999-)

Also during the telling of origins of the dirty joke, the American rock band REO Speedwagon (1967-) is mentioned and a small portion of their 1980 song, ‘Take It On The Run’, is heard.

Peter's voice over offers to play another of their songs, 1978's ‘Time for Me to Fly’ from the album ‘You Can Tune a Piano but You Can't Tuna Fish’ but they are stopped by the lead singer Kevin Cronin.

The lead singer from Asia (1981–1986)(1989–Present) (as Peter calls him) or John Payne steps in and asks to play one of their songs. The song that plays is ‘Only Time Will Tell’

Cleveland says the man who he heard the dirty joke from was named Sal Russo.
While perhaps simply a coincidence, Sal Russo is the co-founder of the Tea Party Express, which is a California-based group founded in the summer of 2009 to support the Tea Party Movement

Peter: ...and you want to chase us down the street as we're pulling away, you know where to find us

The scene that follows Peter's line of Cleveland doing exactly what Peter described is a direct parody of the opening of the 70's TV show, ‘What's Happening!’ (1976-1979), complete with the intro music.

Cleveland replaces the character of Freddie "Rerun" Stubbs played by Fred Berry (1951-2003)

During the guys' game of ‘Would You Rather’, singer Amy Winehouse (1983-2011) and CNN newsman Anderson Cooper (1967-) are mentioned.

Theoretical physicist Stephen Hawking (1942-), billionaires Bill Gates (1955-) and Warren Buffet (1930-) are apparently members of the Secret Order of Dirty Joke Writers.