Figures from the Publishers Association show sales of digital books in the UK are soaring.
The sale of ebooks and audio book downloads shot up from £4m to £16m in 2010.
Academic and professional books still dominate overall digital sales, with a sum of £180m last year. Total book sales hit £3.1bn.
The increased digital sales suggest devices such as Amazon’s Kindle and Sony Reader are making an impact on the market.
Traditional print book markets remain popular in the UK. However, in the US, electronic books outsold hardbacks and paperbacks in February.