Question: What producer do both "The Zeta Project" and "Batman Beyond" have in common?

Context paragraphs:
Batman Beyond: Batman Beyond (known as Batman of the Future in Europe, Latin America, Australia, and Asia) is an American animated television series developed by Bruce Timm, Paul Dini, and Alan Burnett and produced by Warner Bros.  Animation in collaboration with DC Comics as a continuation of the Batman legacy.  Depicting a teenaged Batman in a futuristic Gotham City under the tutelage of an elderly Bruce Wayne, the series began airing on January 10, 1999, and ended its run on December 18, 2001.  After 52 episodes spanning three seasons and one direct-to-video , the series was put on hold for the "Justice League" animated series, despite the network having announced plans for a fourth season.

Batman Beyond: Return of the Joker: Batman Beyond: Return of the Joker (also known as Batman of the Future: Return of the Joker in Europe and Australia) is a 2000 American direct-to-video superhero animated film featuring the comic book superhero Batman and his archenemy, the Joker.  It is set in the continuity of the animated series "Batman Beyond", in which Bruce Wayne has retired from crime fighting, giving the mantle of Batman to high-school student Terry McGinnis, and serves as a sequel to both "" and "The New Batman Adventures".  As in the TV series, Will Friedle and Kevin Conroy star as Terry McGinnis and Bruce Wayne, respectively, and Mark Hamill, who voiced the Joker opposite Conroy in "Batman: The Animated Series" and "The New Batman Adventures", reprises his role.

Diedrich Bader: Karl Diedrich Bader (born December 24, 1966) is an American actor, voice actor, and comedian who has played supporting roles in comedies such as "Office Space", "Napoleon Dynamite", "The Drew Carey Show", "Veep", and "Outsourced".  He is also a voice-over artist for multiple animated series; some of his roles include Batman on "" and "", android Zeta in "The Zeta Project", Warp Darkmatter in "Buzz Lightyear of Star Command", the Fiskerton Phantom in "The Secret Saturdays", and his recurring role as Hoss Delgado in "The Grim Adventures of Billy and Mandy".

Dan Riba: Daniel Esteban “Dan” Riba (born 1960) is an American television storyboard artist and director of animated cartoons.  He is best known for his work on "The Real Ghostbusters", "C.O.P.S.", "", "", "The New Batman/Superman Adventures", "Batman Beyond", "", "Justice League", "Justice League Unlimited", "Ring Raiders", "Freakazoid", "The Zeta Project", "Mister T" and all animated spinoffs of "ALF".  He has also directed "The Super Mario Bros.  Super Show! " and several "", "" and "" episodes.

Magnussoft ZETA: magnussoft ZETA, earlier yellowTAB ZETA, was an operating system formerly developed by yellowTAB of Germany based on the Be Operating System developed by Be Inc.; because of yellowTAB's insolvency, ZETA was later being developed by an independent team of which little was known, and distributed by magnussoft.  As of February 28, 2007 the current version of ZETA is 1.5.  On March 28, 2007, magnussoft announced that it has discontinued funding the development of ZETA by March 16, because the sales figures had fallen far short of the company's expectations, so that the project was no longer economically viable.  A few days later, the company also stopped the distribution of ZETA in reaction to allegations that ZETA constituted an illegal unlicensed derivative of the BeOS source code and binaries.

Liz Holzman: Liz Holzman (February 9, 1953 – August 11, 2014) was an American film producer and director.  She has won the Emmy Award three times, once for her work on the Warner Bros. animated television show "Pinky and the Brain" and twice for "Animaniacs".  Holzman also received an Emmy nomination as a writer for "Animaniacs" and an Annie Award nomination for her direction of "Animaniacs".  Among her other production credits are the animated series "Baby Blues" and "The Zeta Project".

Batman Beyond (comics): The Batman Beyond concept—featuring the fictional character Terry McGinnis as Batman and based on the television series of the same name—has appeared in various DC Comics publications.  These include a six-issue miniseries from 1999, a 24-issue series that ran from 1999 to 2001, the 2010 "Hush" arc in comic books by DC Comics, and a 2011 eight-issue series.  A short-running series titled "Batman Beyond Unlimited" became the fifth.  "Batman Beyond 2.0" (2013) is the sixth series to feature the character.

The Zeta Project: The Zeta Project is an American science fiction animated television series produced by Warner Bros.  Animation.  It first aired on Kids' WB in January 2001.  It is a spin-off series based on the character Zeta from the "Batman Beyond" episode of the same name.  Consequently, it is set in the DC animated universe.  The show was created by Robert Goodman and Warner Bros.  Animation.

The Batman Adventures: Mad Love: The Batman Adventures: Mad Love is a one-shot comic book written by Paul Dini (writer on "" and "Batman Beyond") and Bruce Timm (executive producer on "The New Batman/Superman Adventures" and the co-creator of "Batman: The Animated Series").  Set in the continuity of "The Batman Animated Series", it won an Eisner Award for "Best Single Story" in 1994.  It was later adapted (with minor alterations for pacing) as an episode of the animated series "The New Batman Adventures".

Zeta (wasp): "Zeta" is a small neotropical genus of potter wasps currently containing 4 species.  Three of them have restricted distributions: "Zeta confusum" is found only in Cuba; "Zeta abdominale" is spread through several Caribbean Islands (Jamaica, Hispaniola, Puerto Rico, Virgin Islands and Antigua, with three presently recognized subspecies) and "Zeta mendozanum" is restricted to the Monte and Patagonia regions of Argentina. " Zeta argillaceum", on the other hand, is a very common, widespread and variable species found in the continental Americas from the southern United States (where it was probably introduced) to central Argentina.  The wide range of color variation of this species has led to the recognition of a number of subspecies and varieties currently treated as simple synonyms.

Supporting paragraphs: The Zeta Project Batman Beyond
Answer: Warner Bros