Users can also peruse more than 150 supplementary texts, ranging from reference works to contemporary reviews of Darwin's books, obituaries and recollections.

BBC: NEWS | Science/Nature | Charles Darwin's works go online

He saw these drawings as documentary and reference material, not as works of art.

WSJ: Ancient Modernism | 'Louis Kahn: The Power of Architecture' | Vitra Design Museum, Germany | By Colin Amery

Its third great achievement is the breadth and thoroughness of its reference, thousands of entries on writers and their works which combine authority and detail with insight.

ECONOMIST: Fantasists

NetApp works with both Cloudera and another Hadoop company, Hortonworks (note the Dr. Seuss elephant reference).

FORBES: How Hadoop Makes Short Work of Big Data