Roughneck Brian Waldner is covered in mud and oil while wrestling pipe on a True Company oil drilling rig outside Watford, North Dakota, October 20, 2012. Thousands of people have flooded into North Dakota to work in state's oil drilling boom. Picture taken October 20, 2012. REUTERS/Jim Urquhart (UNITED STATES - Tags: ENERGY BUSINESS EMPLOYMENT) Published: Říj. 22, 2012, 1:40 odp. | Foto: Reuters