he worked in almost every genre, though large-scale forms lie at the heart of his catalogue with seven symphonies, two dozen concertante works and eight ballet scores to his name . his numerous concerti include four for his own instrument, the piano (1966–76), three for one or two violins (1959, 1980, 2003) as well as for viola (1962), harpsichord (1968), oboe d'amore (1972), clarinet (1977), orchestra (1982), trumpet (1987) and flute (1990), and double concertos for viola and cello (1965) and clarinet and oboe (1988). his chamber works include seven string quartets, the third of which (1979) was inspired by the landscape of the lake district . his solo instrumental music was mainly written for the piano; he composed 13 studies for the instrument, including "gaudí" (1970), inspired by the architect; "mosaic" (1980), inspired by islamic art; and a series of seven (2000–9) each explicitly drawing inspiration from a different composer (; }. other significant piano works include the "haydn variations" (1983), written to commemorate the 250th anniversary of haydn's birth (; ; ).