Paul McCartney, Elton John, and Keith Richards were among the many people paying tribute to Shelley Lazar, the founder of SLO Ticketing who passed away Sunday after a battle with cancer. Lazar worked closely with many major artists — also including the Rolling Stones, Beyonce and Barbra Streisand— and was a pioneer in the business of premium ticketing and VIP programs. She was affectionately known as “The Ticket Queen” — or “MFTQ,” as she was dubbed by Richards.

Early Monday, McCartney posted a pair of photos of himself with Lazar, writing, “Fond fun memories of our lovely MF Ticket Queen, Shelley x.” McCartney also paid tribute to her during his concert in Lazar’s adopted hometown of San Francisco in 2014, dedicating a cover of the Weavers’ hit “San Francisco Bay Blues” to her; she is seen in the video waving and blowing kisses to him.

Elton John posted on Instagram Sunday: “Very sad news today with the passing of Shelley Lazar. She looked after my tickets for years, and worked with such greats as the Rolling Stones and Paul McCartney. Why? Because she was the very best and a legend in her field. She will be deeply missed by the legions who loved her.”

Richards also honored the late SLO Ticketing founder.

“Such a sad day for all who knew her. Shelley was the kindest, most generous and loved lady in the business,” he said in a statement. “She had an amazing sense of humor. She was a member of our family for so long, it seems impossible that she is no longer with us, leaving a huge hole in the universe. May she rest in peace.”

“Shelley Lazar was like no other,” Jimmy Fallon tweeted. “Really gonna miss her.”

Social media, particularly her Facebook page, is filled with loving tributes.

While no details were immediately available, a public tribute to Lazar is expected in the coming weeks.