Steely Dan's previously announced Rockabye Gollie Angel Tour has been extended into the summer, and will now include dates with Elvis Costello.

These newly confirmed shows will pick up on July 6 at Red Rocks Amphitheater in Morrison, CO, and continue through Aug. 12 at West Palm Beach, FL. A complete list of dates and stops is below.

Costello has long professed his admiration for Steely Dan, placing their 1973 album 'Countdown To Ecstasy' on his list of "500 Albums You Need" for Vanity Fair in 2000 -- and covering their song 'Show Biz Kids,' as well. Costello and Steely Dan's Donald Fagen also took part in the late Levon Helm's loose jam sessions, called Midnight Rambles.

Steely Dan had already confirmed eight separate concerts beginning in April, highlighted by a surprise appearance at Coachella. Costello, who will appear with his band the Imposters, is not part of that April run.

Steely Dan and Elvis Costello 2015 Tour Dates:

7/6 - Morrison, CO
7/9 - Auburn, WA
7/11 - Mountain View, CA
7/13 - Los Angeles, CA
7/15 - Albuquerque, NM
7/17 - Austin, TX
7/18 - Houston, TX
7/19 - Dallas, TX
7/22 - St. Louis, MO
7/24-25 - Highland Park, IL
7/27 - Clarkston, MI
7/28 - Cuyahoga Falls, OH
7/30-31 - Boston, MA
8/1 - Holmdel, NJ
8/3 - Camden, NJ
8/5 - Bristow, VA
8/6 - Raleigh, NC
8/8 - Nashville, TN
8/9 - Atlanta, GA
8/11 - Tampa, FL
8/12 - West Palm Beach, FL

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