Question: Which chain was founded first Blackjack Pizza or Valentino's ?

Context paragraphs:
Peppes Pizza: Peppes Pizza is a Norwegian pizza chain that serves American style and Italian style pizza.  Peppes is the largest pizza chain in Scandinavia.  The restaurant was founded by two Americans, Louis Jordan and his wife Anne from Hartford, Connecticut.  The restaurant chain is part of Umoe Catering As which consists of restaurants such as Burger King, TGI Fridays, La Baguette and Cafe Opus.  Peppes Pizza is one of the first restaurants that brought foreign food to Norway.  9 million pizzas are served by Peppes each year with deliveries in 11 cities in Norway.  Their menu was first put online in March 1995.  The servings have been described as enough for two people and that the pizza chain is "a cut above the rest".

Papa Murphy's: Papa Murphy's, a business based in Vancouver, Washington, United States, is a take-and-bake pizza company.  It began in 1995 as the merger of two take-and-bake pizza companies: Papa Aldo's Pizza (founded in 1981) and Murphy's Pizza (founded in 1981).  The company and its franchisees operate more than 1,300 outlets in the United States and Canada.  Papa Murphy's is the fifth-largest pizza chain in the United States.

Rabbe Grönblom: Rabbe Anders Grönblom (May 3, 1950 Helsinki, Finland – June 29, 2015) was a Finland-Swedish businessman who started a successful pizza business in Vaasa, Finland.  His first company—a pizzeria—was called "O sole mio" and it was founded in 1976 in the center of Vaasa.  From there he expanded to a pizza franchise chain first called "Pizzeria N:o 1".  He was known as the "Pizza-emperor" (Pizzakeisari in Finnish), because he was the founder of a well known pizza franchise chain called Kotipizza which was the new name of "Pizzeria N:o 1" which expanded fast outside of Vaasa.  The chain is said to be the biggest one in the Nordic countries.  He was also the founder of a shipping company called RG Line, a hotel chain called Omenahotelli and another pizza chain called Golden Rax Pizzabuffet.  Most of his companies are subsidiaries of Grönblom International LTD, where Rabbe Grönblom acted as director.  Golden Rax Pizzabuffet however is nowadays a part of Finland's largest hotel & restaurant company Restel Oy Ltd, where Rabbe Grönblom sat on the board.  He was also on the board of the Finnish tyre company Nokian Renkaat (since 2003).

Arnold Snyder: Arnold Snyder is a professional gambler and gambling author.  He was elected by professional blackjack players as one of the seven original inductees into the Blackjack Hall of Fame which is hosted at Barona Casino for his record as a blackjack player and his innovations in professional gambling techniques.  He was the first blackjack authority to publish the importance of deck penetration (depth of the deal) in card counting, in his 1980 book "The Blackjack Formula".  He was also the first blackjack researcher to publish (in "Blackjack Forum", 1981–1983) that radical simplification of blackjack card counting systems did not hurt earnings.

Pizza 73: Pizza 73 is a Canadian restaurant chain that offers a number of different styles of pizza, along with chicken wings.  It has been operated by Pizza Pizza since 2007.  Toronto-based Pizza Pizza had acquired the restaurant for a total of $CAN70.2 million.  There are 89 locations throughout Western Canada, which include the provinces of British Columbia, Alberta, and Saskatchewan.  The restaurant's name originates from its original phone number: 473–7373.  Founded by David Tougas and Guy Goodwin in 1985, Pizza 73 is headquartered in Edmonton, Alberta, Canada.

Shakey's Pizza: Shakey's Pizza is a pizza restaurant chain based in the United States.  Founded in 1954, it was the first franchise pizza chain in the United States.  The chain currently has about 500 stores globally, and about 60 in the United States.

Valentino's: Valentino's is a regional Italian restaurant chain based in Lincoln, Nebraska.  Valentino's was founded by Val and Zena Weiler in 1957.  The restaurant was purchased by two Lincoln families in 1971 and began franchising additional locations.  The first carry-out store opened in 1990, and many of the full-scale restaurants converted to the buffet concept in the early-2000s.

Happy Joe's: Happy Joe's Pizza & Ice Cream Parlor is an American pizza parlor chain based in Bettendorf, Iowa.  The restaurant chain was founded in 1972 by Lawrence Joseph "Happy Joe" Whitty, a former Shakey's Pizza manager.  Its 61 restaurants are mostly located in the Midwestern United States (in Iowa, Illinois, Missouri, Minnesota, North Dakota and Wisconsin). , although the company is also present in Arizona.  The idea for Happy Joe's came from a combination of a pizza parlor and ice cream palace.

Pizza Ranch: The Pizza Ranch, Inc., founded in 1981, is a "fast casual" restaurant chain.  Pizza Ranch offers pizza, chicken, a salad bar, and a pizza and chicken buffet.  Pizza Ranch has over 200 locations in Colorado, Illinois, Iowa, Kansas, Michigan, Minnesota, Missouri, Montana, Nebraska, North Dakota, South Dakota, Wisconsin, and Wyoming.  Pizza Ranch is the largest regional pizza franchise in Iowa, Minnesota, North Dakota, and South Dakota.

Blackjack Pizza: Blackjack Pizza is a Colorado-based pizza delivery chain founded in 1983 by a former Domino's Pizza employee, Vince Schmuhl, because Domino's Pizza was the only major pizza delivery company in the Rocky Mountain region and he thought customers would appreciate an alternative.  The pizza chain is the largest in Colorado with 800 employees, some of whom work part-time.  On January 1, 2013, Blackjack Pizza was acquired by Askar Brands.

Supporting paragraphs: Valentino's Blackjack Pizza
Answer: Valentino's