Question: Who was the former chairman of a Venezuela-owned American refiner?

Context articles: Charles Dunstone
Jack So
Citgo
Edward Whitacre Jr.
The W. Alton Jones Cell Science Center
Peter Brabeck-Letmathe
Ian Lang Livingstone
Daniel Carp
Charles O. Holliday
Richard C. Kessler

Sir Charles William Dunstone, CVO (born 21 November 1964) is the co-founder and former chairman of mobile phone retailer Carphone Warehouse, former chairman of multinational electrical and telecommunications retailer and services company Dixons Carphone (formed on 7 August 2014 by the merger of Dixons Retail and Carphone Warehouse), and executive chairman of the TalkTalk Group.
Jack So Chak-kwong, GBM, GBS, JP () is the chairman of the Board of Airport Authority Hong Kong from June 2015.
 He is a former chairman and Executive Director of the Hong Kong Trade Development Council (HKTDC), former chairman and Chief Executive of the MTR Corporation, and former Deputy chairman and Group managing director of PCCW.
Citgo Petroleum Corporation (or Citgo) is a Venezuelan-owned American refiner, transporter and marketer of transportation fuels, lubricants, petrochemicals and other industrial products.
 The company has its American headquarters in the Energy Corridor area of Houston, Texas.
Edward Earl "Ed" Whitacre Jr. (born November 4, 1941) is the former Chairman and CEO of General Motors.
 He is also a former chairman of the board and chief executive officer of AT&T Inc., previously Southwestern Bell Corporation (SBC).
 He served as national president of the Boy Scouts of America from 1998 to 2000.
 On September 1, 2010, Whitacre stepped down as CEO, and retired as chairman of the board by the end of 2010.
The W. Alton Jones Cell Science Center (1971–1995) was a non-profit research and education center on 10 Old Barn Road in Lake Placid, New York.
 The Center was established by a gift of 34 acre of land and $3 million to the Tissue Culture Association from the W. Alton Jones Foundation through efforts of Nettie Marie Jones, widow of W. Alton Jones who was former chairman of the Board of Cities Service Company (see Citgo).
 The original tax-free gift was accompanied by the institutional charter that use of the facility would be restricted forever to non-profit activities related to research and education on the biology of cells.
Peter Brabeck-Letmathe (born 13 November 1944) is an Austrian businessman.
 He is the chairman emeritus, former chairman and CEO of the Nestlé Group, and former chairman of Formula One.
Ian Lang Livingstone, CBE, DL (born 23 February 1938) is a Scottish businessman; former Chairman of the board of Motherwell College; former Chairman of Motherwell Football Club; former Chairman of Lanarkshire Health Board; and former Chairman of the Lanarkshire Development Agency.
Daniel Allen 'Dan' Carp (born 1948) is the former Chairman and Chief Executive Officer of the Eastman Kodak Company.
 Carp served as the Chairman of the Board of Delta Air Lines, replacing former Chairman Gerald Grinstein.
 A native of Wytheville, Virginia, Carp currently lives in Naples, Florida.
Charles Otis "Chad" Holliday, Jr. (born March 9, 1948) is an American businessman, former chairman of Bank of America and former chairman, former chief executive officer and a former director of E. I. du Pont de Nemours and Company (DuPont).
 He is chairman emeritus of the U.S. Council on Competitiveness and chairman of the Business Roundtable's Task Force for Environment, Technology and Economy.
 Holliday is also a founding member of the International Business Council and serves on the board of advisors of the Nicholas Institute for Environmental Policy Solutions.
Richard C. Kessler is an entrepreneur in the field of hotel development and operations.
 Kessler has been Chairman and CEO of The Kessler Enterprise, Inc. since 1984.
 He is also Former Chairman, President and CEO, Days Inn of America, Inc. and Former Chairman of Lutheran Brotherhood.