LAMA by Fredrick R. Hyde-Chambers (McGraw-Hill: $16.95). This novel has received rare praise for a piece of fiction. "He has sung our song for us." Those are the official words of the Office of the Dalai Lama, Central Tibetan Secretariat. The author has thoroughly researched a brutal chapter of history--the often savage and always thorough oppression of Tibet by the Chinese People's Liberation Army in the late 1950s. Tibetan Buddhists have centuries of nonviolence as a basis of their culture, and this was no match for the Chinese Communist invasion of their isolated homeland north of the Himalayas. Action here centers on the fictional Tsun Rinposhay, former bandit, resistance worker and the abbott of a Buddhist monastery. He journeys against incredible obstacles in a desperate attempt to get word to the United Nations that Tibet needs help. Along the way are the horrors of the icy and unforgiving mountain passes, the constant fear of being pursued by the invaders, the torture and death of his friends. The background of Tsun's story is a tapestry of brutality, the slaughter of entire villages, the vengeance and grief of a people who can never hope to win their struggle, the systematic annihilation of an entire culture, save those thousands of refugees who fled to neighboring India and Nepal. For romantic interest, and relief from the grimness of the tale, Tsun has a couple of interesting women in his life who do their best to test his vows of celibacy. In its density and the oppressive sadness of the subject, the novel makes for rather heavy reading, but it has sufficient power of characterization and action to keep one reading.