These are a few books and texts which I recommend:
Autobiography of a Yogi by Paramahansa Yognanda
Play of Consciousness by Swami Muktananda.
Meditate: Happiness Lies Within You by Swami Multananda
The Bhagavad Gita – Many Translations –
Courage and Contentment by Gurumayi Chidvilasananda
Nityananda, The Divine Presence by M.U Hatengdi
Consciousness is Everything by Swami Shankarananda
The Splendor of Recognition by Swami Shantananda