What is the ruling on wearing the khimar, and what are the books that help in adhering to the hijab and prayer?

The head covering (khimar) that covers the head and chest is obligatory for a mature Muslim woman when she goes out, or in the presence of non-mahram men, or when praying, due to the Almighty’s saying: ﴿And let them draw their headcovers over their bosoms﴾ [An-Nur: 31], and due to the saying of the Prophet, peace and blessings be upon him: "Allah does not accept the prayer of a menstruating woman except with a head covering." We recommend reading books such as: "A Treatise on the Hijab of the Muslim Woman in Prayer" by Ibn Taymiyyah and Al-Albani, and "A Treatise on the Hijab" by Ibn Baz and Al-Uthaymeen, and "The Return of the Hijab" by Al-Muqaddam. And for prayer, books such as: "Prayer" by Ibn Al-Qayyim, and "The Four Pillars" by Al-Nadwi, and "Prayer, Why?" by Al-Muqaddam.