Analysis of information sources in references of the Wikipedia article "Хорасанские курды" in Russian language version.
In Khurasan the difficulty is still greater because there are no distinct sub-dialects, and the idiom of the Kurds appears practically uniform. Many sub-sections are closely connected with the Turks, and experience real difficulty whether they are of Kurdish or Turkish nationality(...) Of the four tribes which are traditionally regarded as the original, namely 'Amarlu, Za'faranlu, Shadillu and Kaiwanlu, the first and last appear to-day as small tribes, while the other two are mostly Turkish-speaking and have ceased to be regarded as Kurds.
In Khurasan the difficulty is still greater because there are no distinct sub-dialects, and the idiom of the Kurds appears practically uniform. Many sub-sections are closely connected with the Turks, and experience real difficulty whether they are of Kurdish or Turkish nationality(...) Of the four tribes which are traditionally regarded as the original, namely 'Amarlu, Za'faranlu, Shadillu and Kaiwanlu, the first and last appear to-day as small tribes, while the other two are mostly Turkish-speaking and have ceased to be regarded as Kurds.
