Britannica, IstanbulLưu trữ ngày 18 tháng 12 năm 2007 tại Wayback Machine: When the Republic of Turkey was founded in 1923, the capital was moved to Ankara, and Constantinople was officially renamed Istanbul in 1930.
Britannica, IstanbulLưu trữ ngày 18 tháng 12 năm 2007 tại Wayback Machine: When the Republic of Turkey was founded in 1923, the capital was moved to Ankara, and Constantinople was officially renamed Istanbul in 1930.