Question: What date did the Beatles perform their Rooftop Concert at the Apple Building?
About the article "Let It Be", section "Recording sessions".

Candidate passages:
"Dig a Pony" is a song by the Beatles, originally released on their 1970 album "Let It Be".
"Dig a Pony" was the penultimate song played at the concert on the rooftop of Apple Studios in Savile Row, London on 30 January 1969. 
The Beatles' rooftop concert was the final public performance of the English rock group the Beatles.
On 30 January 1969, the band, with keyboardist Billy Preston, surprised a central London business district with an impromptu concert from the roof of Apple headquarters at 3 Savile Row.
In a 42-minute set, the Beatles played nine takes of five songs before the Metropolitan Police Service forced them to stop.
Footage from the performance was later used in the 1970 documentary film "Let It Be". 
A week later the band agreed to Harrison's terms for returning to the group, which included abandoning the cold and cavernous soundstage at Twickenham.
Sessions resumed on 22 January when the Beatles moved to Apple Studios.
Multi-track recording began on that date and continued until 31 January.
Harrison brought in keyboardist Billy Preston to ease tensions and supplement the band for the live performances.
Preston worked with the Beatles throughout their stay at Apple Studios.
The live concert idea culminated with the Beatles and Preston performing on 30 January on the rooftop of the Beatles' Apple Building at 3 Savile Row before a small audience of friends and employees.
The performance was cut short by the police after complaints about noise.
The complete concert has circulated among bootleg collectors for many years.
Three numbers recorded at the rooftop concert, "Dig a Pony", "I've Got a Feeling" and "One After 909", do appear on the album, while several spoken parts of the concert appear between tracks that were recorded in studio.
The band played hundreds of songs during the "Get Back"/"Let It Be" sessions.
Aside from original songs ultimately released on the "Let It Be" album, there were early versions of many songs that appeared on "Abbey Road", including "Mean Mr. Mustard", "She Came in Through the Bathroom Window", "Sun King", "Polythene Pam", "Golden Slumbers", "Carry That Weight", "Something", "Maxwell's Silver Hammer", "Oh!
Darling", "Octopus's Garden", and "I Want You (She's So Heavy)".
Still others would eventually end up on Beatles' solo albums, including Lennon's "Jealous Guy" (called "Child of Nature" at the time and originally written and rehearsed for the "White Album") and "Gimme Some Truth", Harrison's "All Things Must Pass", "Isn't It a Pity", "Let It Down" and "Hear Me Lord", and McCartney's "Another Day", "Teddy Boy", "Junk" (originally written for the "White Album") and "The Back Seat of My Car".
Much of the band's attention was focused on a broad range of covers, extended jams on 12-bar blues, and occasional new efforts such as Lennon's uncompleted "Madman".
These included classical pieces such as Samuel Barber's "Adagio for Strings", jazz standards such as "Ain't She Sweet", and an encyclopaedic array of songs from the early rock and roll era such as "Stand By Me", "Words of Love", "Lonely Sea", "Bésame Mucho" by Mexican composer Consuelo Velázquez (a song that was part of The Beatles' repertoire in the early days) and "Blue Suede Shoes".
Multiple Bob Dylan songs were also played, including "Positively 4th Street", "All Along the Watchtower" and "I Shall Be Released".
Only a handful of these were complete performances; the vast majority were fragmentary renditions with at most a verse or two of misremembered lyrics.
The rehearsals and recording sessions were filmed and formed the basis of the Beatles' film of the same name.
Two songs appearing on the album were not recorded during the Apple Studios sessions.
"Across the Universe" had been recorded at EMI Studios in February 1968, and "I Me Mine" was not recorded until January 1970 after John Lennon's unannounced departure from the group.
The episode makes several references to The Beatles.
Their first album, "Meet the Be Sharps", is a parody of the "Meet the Beatles" album.
Moe's Tavern changes its name to Moe's Cavern, a reference to the Cavern Club in Liverpool where The Beatles frequently performed in the early 1960s.
Chief Wiggum, thrown out of the band because he was "too Village People", mirrors Pete Best.
Best was an early member of The Beatles but was replaced by Ringo Starr.
The cover of "Bigger Than Jesus", The Be Sharps' second album, features the group walking on water, which is a direct parody of the art on The Beatles' album "Abbey Road".
The name is a reference to a controversial quote made by John Lennon in 1966.
Bart references this by asking, "What did you do lose your popularity?
Screw up like The Beatles and say you were bigger than Jesus?
", to which Homer replies "All the time.
That was the title of our second album."
At the end of the episode, the album's back cover is revealed, on which Homer is seen turned away from the camera, as opposed to the rest of the band.
This is a parody of the "Sgt.
Pepper's Lonely Hearts Club Band" LP reverse, in which Paul McCartney is in the same position.
Barney's Japanese conceptual artist girlfriend is a parody of Yoko Ono.
Their song repeats the phrase "Number 8" and a burp by Barney, a reference to The Beatles' "Revolution 9".
The group performing atop Moe's Tavern at the end of the episode is a parody of The Beatles' impromptu concert on the Apple Corps rooftop during their "Get Back" recording sessions in 1969, hence George Harrison's line, "It's been done."
In addition, The Be Sharps are wearing the same outfits as The Beatles during the rooftop concert scene: Barney in a brown fur coat (John), Homer in a bright red coat (Ringo), Skinner in a black suit (Paul), and Apu in a black coat with green trousers (George).
After the performance, Homer says, "I'd like to thank you on behalf of the group and I hope we passed the audition", paraphrasing a quote by John Lennon at the end of The Beatles rooftop performance.
At the swap meet, Mayor Quimby says "Ich bin ein Springfield Swap Meet Shopper", a parody of John F. Kennedy's famous Cold War quote.
Homer browses through a box with items that cost five cents each.
These include the United States Declaration of Independence, a copy of Action Comics #1, a complete block of Inverted Jenny misprint postal stamps, and a Stradivarius violin.
Principal Skinner tries on a prison mask with the number 24601, notable as Jean Valjean's prison number in "Les Misérables".
Homer buys Grampa a pink Cadillac, just as Elvis Presley did for his mother.
One of the late night television shows Chief Wiggum watches is Johnny Carson doing his Carnac the Magnificent routine.
Homer mentions that 1985 was the year that Joe Piscopo left the NBC sketch show "Saturday Night Live".
Moe sells oyster shells at the swap meet that resemble Lucille Ball.
Homer begins telling the story of The Be Sharps by saying, "Rock and roll had become stagnant.
'Achy Breaky Heart' was seven years away; something had to fill the void.
That something was barbershop."
At the Grammy ceremony, Spinal Tap, Michael Jackson (Leon Kompowsky) and George Harrison are all at the post awards reception and MC Hammer in the audience.
While Bart and Lisa browse through LP albums at the swap meet, they find a recording of "Yankee Doodle" by Melvin and the Squirrels, a band that spoofs "Alvin and the Chipmunks" as well as a Spinal Tap album. 
"The Longest Cocktail Party: An Insider's Diary of the Beatles, Their Million-dollar Apple Empire and Its Wild Rise and Fall" (ISBN 1-84195-602-3) is a rock history book by Richard DiLello, published in 1973 by Playboy Press, and reprinted in 1981 and 2005.
"The Longest Cocktail Party" is one man's account of the history of The Beatles company Apple Corps, the breakup of the Beatles, and the beginning of their solo careers.
The title is a reference to the press office's habit of entertaining members of the media, and the company's potential business partners, with expensive drinks, luncheons and perks — which ultimately led to a financial and spiritual hangover, as did the unrealised potential of the company.
DiLello served as the "house hippie" (formally termed Client Liaison Officer; a sort of in-house youth consultant and gofer) at Apple's Savile Row headquarters, from 1968 until 1970, becoming one-on-one acquainted with each of the Beatles, many of their wives and girlfriends, and also the inner circle of agents, managers, and others who worked for and with Apple.
These included business manager Allen Klein, attorneys Lee Eastman and John Eastman, road managers (and Apple directors) Mal Evans and Neil Aspinall, press agent and author Derek Taylor, members of Apple bands Badfinger and White Trash, the staff and the countless visitors to the office.
DiLello covers events including the launching parties for Apple Records and artists like White Trash and Mary Hopkin, the ill-fated Apple Christmas party in 1968 (with two Hells Angels as guests), George Harrison instructing Peter Asher in 1969 to look up the band Raven while in New York, the Beatles' rooftop concert appearing in "Let It Be", the lawsuits that began as the Beatles grew apart, and finally the closing of the Apple press office.
His reports are described firsthand, always with a sense of humour, and a sense of hope.
In addition to shooting the cover portrait of Badfinger for their "Straight Up" album, DiLello also went on to write the script for the 1983 Sean Penn film "Bad Boys".
This seemed an obvious avenue for DiLello, as "The Longest Cocktail Party" nearly functions as a film script in itself.
The several appendices to the book include the full text of the self-penned 'interview' issued by Paul McCartney with the prerelease copies of his first solo album ("McCartney"), that effectively announced the band's breakup in April 1970; a discography of Apple Records releases; a list of the Beatles' achievements as recording artists; and text of several British news articles about Apple.
On Friday 7 May 2010, it was confirmed that the book is to be made into a feature film.
It is currently in development by Liam Gallagher's In 1 Productions.