Complex sentence: The "American National Biography" (ANB) is a 24 volume biographical encyclopedia set containing approximately 17,400 entries and 20 million words, first published in 1999 by Oxford University Press under the auspices of the American Council of Learned Societies.
Split into simpler sentences: The "American National Biography" is a 24 volume biographical encyclopedia set containing approximately 17,400 entries and 20 million words. It was published by Oxford University Press under the auspices of the American Council of Learned Societies.