Shareholders of MDU Resources Group, Inc. announced at the company's annual meeting of stockholders elected Dale S. Rosenthal as a new independent director to the company's board. Rosenthal, 64, has experience in the construction industry, having held senior executive positions including strategic director, division president and chief financial officer in an integrated construction company. Rosenthal held various positions for 22 years with Clark Construction Group, LLC, a vertically integrated construction company. She also has served since 2014 as a director of Washington Gas Light Co., a regulated public utility company that is now a subsidiary of AltaGas Ltd. and sells and supplies natural gas in Washington, D.C., and surrounding areas.