Used on No Better Than This, as stated in this August 16, 2010 Bloomington Herald Times article archived on Mellencamp's official website.

He’s never realized that ambition more than with “No Better Than This,” his 25th album. It’s 13 songs written and recorded over 13 days on a 55-year-old Ampex tape recorder using one classic RCA 77 DX microphone. The songs were all laid down on the road during off-days on his 2009 tour of minor league ballparks and off-the-beaten-path venues with compatriots Bob Dylan and Willie Nelson.

It is also mentioned in this August 17, 2010 Music Angle (now Analog Planet) article, also archived on Mellencamp's official website.

Equipped with John Mellencamp's then recently acquired vintage 1/4" reel-to-reel 1955 Ampex 601 mono tape recorder and a pair of iconic 50's era RCA ribbon microphones ( a 77 DX and 44 used singly) presumably supplied by producer T-Bone Burnett, the duo, accompanied by Mellencamp's wife Elaine, who shot the album's cover photo, hit the road during a break in last summer's Bob Dylan-John Mellencamp-Willie Nelson tour to record thirteen freshly penned songs Mr. Mellencamp had written over thirteen prolific days.

Mentioned in this October 11, 2016 Electronic Musician article.

These days he uses three mics on the drums, which, most people would still think of as a pretty minimalist setup. “We usually have an RCA 77DX or an Altec 639 pretty far overhead,” he says. “About three feet or so above the kit, kind of going for a Motown type of sound. And then a kick and a snare mic. We have a small ribbon mic that we put on the kick. It’s an Altec, like the little brother to the 639B, the 671B. We call it the “Mini Bird Cage.” We don’t put it right in front of the kick, but we’ll put it in that spot off to the side of the kick where you might get a little from the bottom of the snare drum and an indirect kick drum sound. Then also an overhead, and a mic pretty much on the snare drum—on top, to blend in, kind of facing away from the hi-hat, just facing the snare, and trying to only get the crack from the snare. And the cymbals and tom toms are kind of in focus because of the overhead, and we have control over the kick and snare.”

Charley Crockett is confirmed to use the RCA 77-DX microphone, as evidenced by its use at Norman Petty Studios, where it was employed for recordings by artists such as Buddy Holly, Waylon Jennings, Roy Orbison, and more.

This mic was used to record the whole of "Gon' Boogaloo", according to the album's liner notes.

I also have an old RCA ribbon mic that I like to throw out of phase intentionally with the Sennheiser.

Visible in this ca. 1955 this photo of Haley.

American rock and roll singer Bill Haley (1925 - 1981), at a microphone, circa 1955. (Photo by Silver Screen Collection/Getty Images)

Mentioned in this Facebook post by SugarHill Recording Studios.

RCA released the 77 DX in 1954. This gem of a mic has a very dynamic frequency response depending on the angle in which it is positioned. It has recorded countless legends including Al Green, Elvis Presley, Frank Sinatra, Johnny Cash and more!! It is still widely used today especially for recording Brass instruments. Come try it for yourself.

In the video titled "Vance Powell: Recording Rock" by Sound On Sound magazine, at the 19:48 mark, Vance Powell demonstrates the use of the RCA 77-DX microphone in recording the track "Loaded Dice & Buried Money."

Used for Coleman's alto saxophone for The Shape of Jazz to Come and Change of the Century, as recounted by sound engineer "Bones" Howe in this February 2004 Sound on Sound interview (the DX is specified later in the article when Tom Waits is discussed).

"I set them up in a square, one in each corner of an imaginary room in the studio, close together, all facing the centre of the square. I had set up the microphones before they got there: I had an RCA 77 on Ornette's alto sax — the white plastic one he was notorious for playing — and a 77 on Don Cherry's pocket trumpet, a Telefunken U47 on Charlie's bass, and the drums were miked with a U47 as an overhead and a 77 over the hat and snare. We were recording live to mono and two-track at the same time. I liked this setup so much that I made sure I wrote it down, and I still have that setup sheet to this day. I would use it to record a lot of albums."

Used to record "Take It As It Come", as is visible in the documentary Charles Bradley: Soul of America at 8:14. The 77-DX is also visible in this photo of Bradley, the music video for "The World (Is Going Up In Flames)" at 1:25 and at 2:40 and the music video for "Heartaches and Pain" starting at 1:04. It is most likely the one at Daptone Records' recording studios, which was mentioned by producer Gabriel Roth in this June 2008 Sound on Sound article.

"There's an old–school feel to the studio, but it's by no means some kind of vintage museum," Roth states. In fact, the gear list is as much serendipitous as it is calculated: there's a newish Rode NT1A large–diaphragm condenser mic, a classic RCA DX77, and an assortment of cheap Radio Shack microphones cohabitating in the mic closet, while an Ampeg Gemini guitar amp made its way to the studio when it literally bumped into Roth as it was being tossed out into a dumpster near a building renovation.

Used for Cherry's pocket trumpet on Ornette Coleman's The Shape of Jazz to Come and Change of the Century, as recounted by sound engineer "Bones" Howe in this February 2004 Sound on Sound interview (the DX is specified later in the article when Tom Waits is discussed).

"I set them up in a square, one in each corner of an imaginary room in the studio, close together, all facing the centre of the square. I had set up the microphones before they got there: I had an RCA 77 on Ornette's alto sax — the white plastic one he was notorious for playing — and a 77 on Don Cherry's pocket trumpet, a Telefunken U47 on Charlie's bass, and the drums were miked with a U47 as an overhead and a 77 over the hat and snare. We were recording live to mono and two-track at the same time. I liked this setup so much that I made sure I wrote it down, and I still have that setup sheet to this day. I would use it to record a lot of albums."

Visible in a trio of photos taken by Ted Williams of Hubbard in the studio. The other two can be found here and here.