Robert Harry van Gent.Online Calendar Converters Based on the Tabular Islamic Calendar. Mathematical Institute, Utrecht University (декабрь 2019). — «It can easily be demonstrated that the so-called 'Kuwaiti Algorithm' was based on the standard arithmetical scheme (type IIa) which has been used in Islamic astronomical tables since the 8th century CE.» Дата обращения: 15 ноября 2020. Архивировано 15 ноября 2021 года.
Robert Harry van Gent.Online Calendar Converters Based on the Tabular Islamic Calendar. Mathematical Institute, Utrecht University (декабрь 2019). — «It can easily be demonstrated that the so-called 'Kuwaiti Algorithm' was based on the standard arithmetical scheme (type IIa) which has been used in Islamic astronomical tables since the 8th century CE.» Дата обращения: 15 ноября 2020. Архивировано 15 ноября 2021 года.