ICAO DOC 8168 OPS - Aircraft Operations - Volume 2 Construction of Visual and Instrument Flight Procedures Ed 7
This volume is intended for the guidance of procedures specialists and describes the essential areas and obstacle clearance requirements for the achievement of safe, regular instrument flight operations. It provides the basic guidelines to States, and those operators and organizations producing instrument flight charts that will result in uniform practices at all aerodromes where instrument flight procedures are carried out.
Corrigendum 1 - 20/11/20
Corrigendum 2 - 21/03/22