APA

Baldwin D. D., Royal R. W., Gill H. S., Esso, World Petroleum Congress (11th. : 1983 : London), Royal R. W., Gill H. S. & ESSO.Drilling high angle directional wells. : .

Chicago

Baldwin Doug D, Royal Ron W, Gill Harmohan S, Esso, World Petroleum Congress (11th. : 1983 : London), Royal Ron W, Gill Harmohan S and ESSO.Drilling high angle directional wells. : .

Harvard

Baldwin D. D., Royal R. W., Gill H. S., Esso, World Petroleum Congress (11th. : 1983 : London), Royal R. W., Gill H. S. and ESSO.Drilling high angle directional wells. : .

MLA

Baldwin Doug D, Royal Ron W, Gill Harmohan S, Esso, World Petroleum Congress (11th. : 1983 : London), Royal Ron W, Gill Harmohan S and ESSO.: . .