Answer the question at the end by quoting:

Cronin was born in Cardross, Dunbartonshire, Scotland, the only child of a Protestant mother, Jessie Cronin (nee Montgomerie), and a Catholic father, Patrick Cronin. Cronin often wrote of young men from similarly mixed backgrounds. His paternal grandparents had emigrated from County Armagh, Ireland, and become glass and china merchants in Alexandria. Owen Cronin, his grandfather, had had his surname changed from Cronague in 1870.
The Citadel (1937), a tale of a mining company doctor's struggle to balance scientific integrity with social obligations, helped to incite the establishment of the National Health Service (NHS) in the United Kingdom by exposing the inequity and incompetence of medical practice at the time. In the novel Cronin advocated a free public health service in order to defeat the wiles of those doctors who "raised guinea-snatching and the bamboozling of patients to an art form." Dr Cronin and Aneurin Bevan had both worked at the Tredegar Cottage Hospital in Wales, which served as one of the bases for the NHS. The author quickly made enemies in the medical profession, and there was a concerted effort by one group of specialists to get The Citadel banned. Cronin's novel, which was the highest-selling book ever published by Victor Gollancz, informed the public about corruption within the medical system, planting a seed that eventually led to reform. Not only were the author's pioneering ideas instrumental in the creation of the NHS, but the historian Raphael Samuel asserted in 1995 that the popularity of Cronin's novels played a substantial role in the Labour Party's landslide victory in 1945. By contrast, according to one of Cronin's biographers, Alan Davies, the book's reception was mixed. A few of the more vociferous medical practitioners of the day took exception to one of its many messages: that a few well-heeled doctors in fashionable practices were ripping off their equally well-off patients. Some pointed to the lack of balance between criticism and praise for hard-working doctors. The majority accepted it for what it was, a topical novel. The press attempted to incite passions within the profession in an attempt to sell copy, while Victor Gollancz followed suit in an attempt to promote the book, all overlooking the fact that it was a work of fiction, not a scientific piece of research, and not autobiographical. In the United States The Citadel won the National Book Award, Favorite Fiction of 1937, voted by members of the American Booksellers Association. According to a Gallup poll conducted in 1939, The Citadel was voted the most interesting book readers had ever read.

What is the citadel?

), a tale of a mining company doctor's struggle to balance scientific integrity with social obligations,

Answer the question at the end by quoting:

Lord Voldemort (; in the films; born Tom Marvolo Riddle) is a fictional character and the main antagonist in J. K. Rowling's series of Harry Potter novels. Voldemort first appeared in Harry Potter and the Philosopher's Stone, which was released in 1997. Voldemort appears either in person or in flashbacks in each book and its film adaptation in the series, except the third, Harry Potter and the Prisoner of Azkaban, where he is only mentioned. Voldemort is the archenemy of Harry Potter, who according to a prophecy has "the power to vanquish the Dark Lord".
Voldemort does not appear in Harry Potter and the Half-Blood Prince, although his presence and actions are felt: he once again declares war, and begins to rise to power once more. He murders Amelia Bones of the Department of Magical Law Enforcement, and begins to target members of the Order of the Phoenix, including Emmeline Vance. Rowling uses several chapters as exposition to establish Voldemort's backstory. In a series of flashbacks, using the pensieve as a plot device, she reveals that Voldemort was the son of the witch Merope Gaunt and a Muggle called Tom Riddle. Riddle abandoned Merope before their child's birth, soon after which Merope died, just hours after giving birth. After living in an orphanage, young Riddle met Dumbledore, who told him he was a wizard and arranged for him to attend Hogwarts. Riddle was outwardly a model student, but was in reality a psychopath who takes sadistic pleasure in using his powers to harm and control people. He eventually murdered his father and grandparents as revenge for abandoning him. The book also discusses Riddle's hatred of "Muggles", his obsession with Horcruxes, and his desire to split his soul to achieve immortality. Rowling stated Voldemort's conception under the influence of a love potion symbolises the prejudicial circumstances under which he was brought into the world. In the main plot of the book, Voldemort's next step is to engineer an assault on Hogwarts, and to attack Dumbledore. This is accomplished by Draco Malfoy, who arranges transportation of Death Eaters into Hogwarts by a pair of Vanishing Cabinets, which bypass the extensive protective enchantments placed around the school. The cabinets allow Voldemort's Death Eaters to enter Hogwarts, where battle commences and Dumbledore is cornered. Hogwarts professor (and re-doubled agent) Severus Snape uses the Killing Curse against Dumbledore when Draco could not force himself to do so.

What happens as he gains power?
He murders Amelia Bones of the Department of Magical Law Enforcement, and begins to target members of the Order of the Phoenix, including Emmeline Vance.