Analysis of information sources in references of the Wikipedia article "Bảng chữ cái ngữ âm NATO" in Vietnamese language version.
p) In alphanumeric call signs avoid phonetic letters that can be confused with another operator designator prefix e.g. D - Delta (The Airline).
p) In alphanumeric call signs avoid phonetic letters that can be confused with another operator designator prefix e.g. D - Delta (The Airline).
