Bernhard Bauer and Detlef Heck และ -. (2015) Price Pressure on Planners? Fees and its Impact on the Planning Quality. ISEC Press:ม.ป.ท.Bernhard Bauer and Detlef Heck และ -. 2015. Price Pressure on Planners? Fees and its Impact on the Planning Quality. ม.ป.ท.:ISEC Press;Bernhard Bauer and Detlef Heck และ -. Price Pressure on Planners? Fees and its Impact on the Planning Quality. ม.ป.ท.:ISEC Press, 2015. Print.