Goo Goo Gai Pan/References

Trivia

The sack of 10,000 dollars must have been all one dollar bills, as there is no other way that it could have so many bills. Also, the ridiculously huge sack of money appears right next to Wu at first. However, it is gone the next time she is shown. But the way this was shown indicates that this was intentional.
Selma's signature is almost as bad as you'd imagine Homer's would be.
Although Selma wants to take care of a child in this episode, she had earlier decided not to bother with kids after trouble with Bart and Lisa in Selma's Choice.
Robert Wagner is the second celebrity this season to host a Troy McClure-esque video. The first was Gary Busey in the previous episode.
Maggie Simpson inexplicably does not appear in this episode while the rest of the family is halfway around the world. However, it is possible that they left Abe Simpson in charge of her while they're gone, as he also does not appear in this episode either.

When Selma says the car is too hot, Burns says it is actually cooler than Guy Lombardo, a famous Canadian band leader.
Mr. Burns says his car once outraced the Flying Finn, Paavo Nurmi, an athlete who won 9 Gold Medals at the 1920, 1924 and 1928 Summer Olympics. Both this and the afore mentioned references are among the many Burns age jokes that have been used throughout the series.
The dragons Homer imagines are white, gold, and red, but at the end the white one is green. That first dragon also resembles the one who appears in Spirited Away.

The title of this episode is a pun on moo goo gai pan, the name of a popular pseudo-Chinese American recipe, based on the Cantonese dish mah gu gai pin, which is composed of fresh button mushrooms and other vegetables with sliced chicken.
China (except for Hong Kong and Macao) uses the Simplified Chinese characters, but many signs in this episode are clearly using Traditional Chinese. However, there are still signs that use Traditional Characters in China.
The correct spelling of the place would be "Tian An Men", not "Tien An Men"(as this is the Wade system).
When Selma stands in front of the tank piloted by Wu, the shot is highly reminiscent of the famous image of the Unknown Rebel blocking the line of tanks during the Tiananmen Square protests.
While flying to China, the plane passes over a monument to "Warrior and spicy chicken pioneer" General Zuo Zongtang.

Flag of the Communist Party of China (first US broadcast of Goo Goo Gai Pan.)

The original broadcast portrayed the body of Mao Zedong covered by the flag of the Communist Party of China with the hammer and sickle (as is the case in the actual mausoleum). However, in later broadcasts the flag was substituted for the Flag of the People's Republic of China
In the Chinese consulate there is a map behind the consulate official showing Taiwan as a separate country, extremely unlikely given the PRC's position regarding Taiwan.
There is a plaque reading, "On this spot in 1989, nothing happened", in Tiananmen Square, a reference to the Chinese Government's denial of the 1989 Tiananmen Square massacre. It is also a reference to the year The Simpsons first aired.
In addition to being a sardonic reference to the massacre, the sign in the square ("On this site in 1989, nothing happened") is a parody of real signs. Available from catalogues, they are mock-historical plaques that say: "On this site in 1897, nothing happened."
What's written on the adoption paper is gibberish, not Chinese, though this may be a play on the fact that computers which do not have Chinese text support installed may transcribe gibberish and random symbols in its place (mojibake).

The aircraft the Simpsons and Selma take to China is not capable of a China to America trip.
Homer drives a car in China, but in China, non-residents are not allowed to drive.
When Homer falls from the chairs he is falling face-down. When he lands on the chairs, he is on his back.