AceShowbiz -

Lady GaGa shared an Instagram photo on Friday, July 18, that showed one of her breasts peeking out of her low-cut white outfit. She was sitting inside a plane and slightly smiling at the camera. Her nipple was also visible.

In the picture, GaGa was wearing a white top with a plunging neckline and no bra. The photo was taken at an angle that gave users a full view of her right boob. The singer sported red lipstick and oversized sunglasses. She captioned the picture with, "FASHUN. Vintage Mugler on the plane Listening to Miles Davis. My favorite is Flamenco Sketches."

Instagram's community guidelines state, "Please do not post nudity or mature content of any kind." It's unclear if the picture was intentionally posted as a statement against the censorship. The singer later deleted the selfie.

Before her departure, the "Fame Monster" singer shared another picture in her all-white designer wear with her darling puppy. She wrote, "On my way to The Yellowstone Club in Montana to see @jeffkoonsstudio for a talk about Art."

Meanwhile, GaGa's former assistant, Jennifer O'Neill, is reportedly writing a tell-all book about the musician. O'Neill worked for GaGa from 2009-11 during the singer's "Monster Ball" tour. She sued her former boss in 2011, claiming that GaGa owed her $393,000 for 7,168 hours of overtime. Page Six insiders said that O'Neill's book deal with Atria Books could be worth up to $1 million.

O'Neill testified that she was expected "to be working and available 24/7" for an annual salary of $75,000. Her duties included administering GaGa's "medicine," "ensuring the promptness of a towel following a shower" and even sleeping in GaGa's bed "because she didn't sleep alone." In a deposition, the singer called O'Neill a "f**king hood rat who is suing me for money that she didn't earn."