New Delhi, Feb 8 The nine-day 19th World Book Fair concluded here on Sunday evening amid a rush of last-minute visitors and a show paying tribute to the cultural diversity of India.

Children sang patriotic songs and enacted skits depicting the country's colourful culture and its rich publishing and knowledge heritage.

The fair opened late at 12 noon because of the Delhi marathon.

An unofficial estimate said the number of footfalls touched nearly 30,000 on the last three days of the fair. No official numbers were made available.

Historian Bipan Chandra, the chairman of the National Book Trust (NBT), which organised the fair and Nuzhat Hassan, the director of the fair, said at a press conference that the volume of business had doubled compared to 2008 and the participation was more than anticipated.

Business in language and Hindi books also boomed, along with publications in English, the NBT officials said.

"The volume of international trade with 35 stalls from 15 countries and business delegations was substantially more than 2008. The bulk of visitors comprised children from not only Delhi and NCR region, but also from places as far as Chandigarh, Karnal, Hapur and Amroha," Bipan Chandra said.

He said in terms of sales, the fair had broken past records.

Publishers, however, rued poor business citing less money in the market and government squeeze on credit to educational institutions as part of an austerity drive.