Question: RefNet features teaching from the theologian of what denomination?
Context: The Evangelical Reformed Church in Transcarpathia is a conservative Reformed denomination in Transcarpathia.  The church was founded in 2006.  The new denomination separated from the Reformed Church in Transcarpathia because the liberal teaching of the church and the unbiblical episcopal government.  The members are ethnic Hungarian.  It has about 200 members in 6 congregations (including congregations in Visk, Beregszász, Beregújfalu) and Bible study classes in 12 villages.  In 2007 the church was registered by the government.  The denomination affirms the Westminster Confession of Faith, Second Helvetic Confession and the Heidelberg catechism.  It has Presbyterian church government, with Synod and with local Presbyterian councils. RefNet, or Reformation Network, is a Christian internet radio station launched as an outreach of Ligonier Ministries in July 2012.  It features Bible teaching from a number of popular evangelical Christian teachers, including Alistair Begg, John MacArthur, Albert Mohler, John Piper, and R.C. Sproul, news updates from respected Christian organizations, Bible readings, audio books, and some selections of sacred and classical music.  The theology of much of the teaching featured on RefNet is distinctly Calvinist or Reformed. Caspar Erasmus (Erich) Schieler (July 14, 1851 – January 13, 1934) was a German theologian, church historian and priest in the late 19th century and early 20th century.  According to documents provided by Mainz Cathedral and the Diocesan Seminary, Schieler studied philosophy and theology at the Episcopal Seminary in Mainz (Closed during the Kulturkampf in 1878), receiving the Doctor of Divinity degree.  Schieler first served as a priest at the age of twenty-five at Mainz, Cathedral ordained under Bishop Wilhelm Emmanuel von Ketteler in the year 1876.  Due to the Kulturkampf, Schieler was interrogated by the German government and forced to pastor his parish in secret, to avoid further attention.  While secretly pastoring in Weisskirchen, Schieler began working on his dissertation: "Magister Johannes Nider", for which he received the degree of Doctor of Theology, Magna cum Laude in Wurzburg, Germany in the year 1886.  Schieler then become the Professor of Moral Theology at Diocesan Seminary of Mainz in Baden-Württemberg.  After breaking from The Catholic Church and converting to Protestantism, Schieler continued writing books and became a pastor in the Lutheran Church, which later merged into the United Church of Christ, a mainline Protestant Christian denomination, with historical confessional roots in the Reformed, Congregational and Lutheran traditions.  Schieler served as a Professor of theology and Latin American and German language and literature at the Mission House College, which later became Lakeland University.  At the request of the Educational Department, Schieler later took up a teaching position at Redfield College, teaching theology in Redfield, South Dakota.  Schieler was then called upon by the German Evangelical Synod of North America, to teach and preach in communities in Hartsburg, Missouri, Hamel and Johannisburg, Illinois and Marion, Wisconsin. Grace Communion International (GCI), formerly the Worldwide Church of God (WCG) (though still registered as Worldwide church of God in the UK and some other regions) and the Radio Church of God, is an evangelical Christian denomination based in Glendora, California, U.S., with the former organizations having had an often controversial influence on 20th century religious broadcasting and publishing in the United States and Europe.  In the years after founder Herbert W. Armstrong's death in 1986, church leaders (though not the congregations) came to the conclusion that many of his doctrines were not biblical.  These doctrines were subsequently rejected by the leadership, but still practiced by a number of church members and the church is now split on doctrine.  The leadership is in full agreement with the statement of faith of the National Association of Evangelicals so that they could join, but not all members agree with the current teaching.  In light of these doctrinal changes, in April 2009, the denomination changed its name to Grace Communion International in the USA to better reflect its new teaching. Robert Charles Sproul ( ; born February 13, 1939) is an American Calvinist theologian, author, and pastor.  He is the founder and chairman of Ligonier Ministries (named after the Ligonier Valley just outside Pittsburgh, where the ministry started as a study center for college and seminary students) and can be heard daily on the "Renewing Your Mind" radio broadcast in the United States and internationally.  "Renewing Your Mind with Dr. R. C. Sproul" is also broadcast on Sirius and XM satellite radio.  In late July 2012, a new Christian internet radio station called RefNet (Reformation Network) was also announced by Ligonier Ministries in an effort to reach "as many people as possible" where Internet access is available. Formal principle and material principle are two categories in Christian theology to identify and distinguish the authoritative source of theology (formal principle) from the theology itself, especially the central doctrine of that theology (material principle), of a religion, religious movement, tradition, body, denomination, or organization.  A formal principle tends to be texts or revered leaders of the religion, while a material principle is its central teaching.  Paul Tillich believed the identification and application of this pair of categories in theological thinking to have originated in the 19th century.  As early as 1845 the Protestant theologian and historian Philip Schaff discussed them in his "The Principle of Protestantism".  They were utilized by the Lutheran scholar F. E. Mayer in his "The Religious Bodies of America" in order to facilitate a comparative study of the faith and practice of Christian denominations in the United States.  This is also treated in a theological pamphlet entitled "Gospel and Scripture" by the Commission on Theology and Church Relations of the Lutheran Church—Missouri Synod. Abu al-Sha'tha Jābir ibn Zayd al-Zahrani al-Azdi was a Muslim theologian and one of the founding figures of the Ibadis, the third major denomination of Islam.  He was from the Tabi‘un, or second generation of Islam, and took leadership of the denomination after the death of Abd-Allah ibn Ibadh. Kulilits was a weekly program shown in ABS-CBN for children.  It features teaching children moral and values to singing new songs to dances and to mathematics.  The show is hosted by Chacha Cañete, Bugoy Cariño along with Izzy Canillo. Union Christian College was a small co-educational college located in Merom, Sullivan County, Indiana.  Founded by the denomination called the Christian Church which eventually merged with the Congregational denomination which later joined with the Evangelical and Reformed Churches to form the United Church of Christ.  It was one of the first co-educational colleges that allowed women to take any class that a man could take.  Other co-educational colleges would only allow their women to study home economics, nursing, teaching, secretarial, etc.  At UCC women could study to be doctors, lawyers, ministers, or home-makers.  UCC was very progressive for its time.  One of its most notable alumni was James M. Hamilton (class of 1890), who became the third president of Montana State University, serving from 1904 to 1919. Penn State Behrend is a state-related public university institution and a Commonwealth campus of Pennsylvania State University located in Erie, Pennsylvania.  The college in recent years has added a number of facilities, including an athletics and recreation center (Junker Center), chapel and carillon (Smith Chapel), astronomy observatory, planetarium (Yahn Planetarium at Penn State Behrend), large residence halls (Ohio and Almy Halls), Knowledge Park at Penn State Behrend, a baseball and softball complex, and a soccer and lacrosse complex.  The $30 million, 160000 sqft Jack Burke Research and Economic Development Center that houses the School of Engineering and the Sam and Irene Black School of Business opened in 2006.  It features teaching and research labs, including the largest academic plastics lab in the United States.  In 2010, the $4 million Robert and Sally Metzgar Admissions and Alumni Center opened.
Answer: American Calvinist