Question: Who wrote a 2014 book about the owners of the  second-largest privately owned company in the United States?
Context: Binford & Mort Publishing is a book publishing company located in Hillsboro, Oregon, United States.  Founded in 1930, the company was previously known as Metropolitan Press and Binfords & Mort.  At one time they were the largest book publisher in the Pacific Northwest.  The privately owned company focuses on books from the Pacific Northwest, and has printed many important titles covering Oregon’s history. ProSieben (] , "sieben" is German for seven) is a commercial television station in Germany.  It is largely distributed by cable and satellite and to a lesser extent digital video broadcasting – terrestrial.  It began operations on 1 January 1989.  Since 2003, the station, part of ProSiebenSat.1 Media.  ProSieben is Germany's second-largest privately owned television company.  Although ProSieben produces some of its programming itself, it also airs many American imports.  On 3 May 2012, ProSieben launched a payTV channel called ProSieben Fun.  A third channel called ProSieben Maxx started broadcasting on 3 September 2013. Beyond Words Publishing is a book publishing company located in Hillsboro, Oregon, United States.  Founded in 1983, the company was unprofitable in its early years, though its works were award winning.  The privately owned company focuses on non-fiction titles in the New Age genre (now generally referred to as mind-body-spirit category), but began as a publisher of coffee table books.  Beyond Words has a national distribution agreement with Simon & Schuster’s Altria Books imprint and has published works by John Gray, Masaru Emoto, and Rhonda Byrne, including her book The Secret. Sons of Wichita: How the Koch Brothers became America's most powerful and private dynasty (2014) is a non-fiction book written by the American journalist Daniel Schulman about the wealthy Koch family and their political activities. New Zealand Mint (Māori: Te Kamupene Whakanao o Aotearoa ) is a privately owned company in Auckland, New Zealand.  It is the only privately owned mint in New Zealand, purchasing refined gold from international sources to produce coins.  The company trades in precious metals including gold bullion, and is a physical storage provider. TransMontaigne Inc., formerly NYSE:TMG, is a oil pipeline and terminal company based in Denver, Colorado.  In 2006, it was the 269th largest company in the United States and as of 2012 it was the 17th largest privately owned company.  On September 1, 2006, it became a wholly owned subsidiary of Morgan Stanley, and subsequently delisted from the New York Stock Exchange.  In 2014, Morgan Stanley sold TransMontaigne to NGL Energy. Banfield Pet Hospital is a privately owned company based in Vancouver, Washington, United States, that operates veterinary clinics.  Part of the Mars, Incorporated family of companies, Banfield owns clinics in the United States, Mexico, and the United Kingdom.  Founded in 1955, the company operates many of its 800 plus clinics inside PetSmart stores.  Banfield is the largest privately owned veterinary practice in the United States.  On April 2, 2014, Banfield Pet Hospital announced its headquarters would be relocating to Vancouver, Washington, from nearby Portland, Oregon. The Koch family ( ) is an American family engaged in business, most noted for their political activities and control of Koch Industries, the second-largest privately owned company in the United States (with 2013 revenues of $115 billion).  The family business was started by Fred C. Koch, who developed a new cracking method for the refinement of heavy crude oil into gasoline.  Fred's four sons litigated against each other over their interests in the business during the 1980s and 1990s. Minnetonka ( ) is a suburban city in Hennepin County, Minnesota, United States, eight miles (13 km) west of Minneapolis.  The population was 49,734 at the 2010 census.  The name comes from the Dakota Indian "mni tanka", meaning "great water".  The city is the home of Cargill, the country's largest privately owned company, and United Healthcare, the state's largest publicly owned company. Lanser Broadcasting is a Zeeland, Michigan based company which owns and operates the WJQK and WPNW radio stations.  It is a privately owned company.  Les Lanser and his son Brad are the sole owners.
Answer: Daniel Schulman