Task: Question Answering
Input (English): Passage: Sir Osbert Lancaster, CBE (4 August 1908 – 27 July 1986) was an English cartoonist, architectural historian, stage designer and author. He was known for his cartoons in the British press, and for his lifelong work to inform the general public about good buildings and architectural heritage. 
The only child of a prosperous family, Lancaster was educated at Charterhouse School and Lincoln College, Oxford, at both of which he was an undistinguished scholar. From an early age he was determined to be a professional artist and designer, and studied at leading art colleges in Oxford and London. While working as a contributor to The Architectural Review in the mid-1930s, Lancaster published the first of a series of books on architecture, aiming to simultaneously amuse the general reader and demystify the subject. Several of the terms he coined as labels for architectural styles have gained common usage, including "Pont Street Dutch" and "Stockbrokers' Tudor", and his books have continued to be regarded as important works of reference on the subject.
In 1938 Lancaster was invited to contribute topical cartoons to The Daily Express. He introduced the single column-width cartoon popular in the French press but not until then seen in British papers. Between 1939 and his retirement in 1981 he drew about 10,000 of these "pocket cartoons", which made him a nationally known figure. He developed a cast of regular characters, led by his best-known creation, Maudie Littlehampton, through whom he expressed his views on the fashions, fads and political events of the day.
From his youth, Lancaster wanted to design for the theatre, and in 1951 he was commissioned to create costumes and scenery for a new ballet, Pineapple Poll. Between then and the early 1970s he designed new productions for the Royal Ballet, Glyndebourne, D'Oyly Carte, the Old Vic and the West End. His productivity declined in his later years, when his health began to fail. He died at his London home in Chelsea, aged 77. His diverse career, honoured by a  knighthood in 1975, was celebrated by an exhibition at the Wallace Collection marking the centenary of his birth and titled Cartoons and Coronets: The Genius of Osbert Lancaster. 
Question: What is the last name of the person whose books have continued to be regarded as important works of reference on the subject of architectural styles?
Output (English): Lancaster.