While a hazy definition of "grey literature" had existed previously, the term is generally understood to have been coined by the researcher Charles P. Auger, who wrote "Use of Reports Literature" in 1975. The literature he referred to consisted of intelligence reports and notes on atomic research produced in vast quantities by the Allied Forces during World War II. In a conference held by the British Lending Library Division in 1978, Auger used the term "grey literature" to describe the concept for the first time. His concepts focused upon a "vast body of documents" with "continuing increasing quantity" that were characterized by the "difficulty it presents to the librarian". Auger described the documentation as having great ambiguity between temporary character and durability, and by a growing impact on scientific research. While acknowledging the challenges of reports literature, he recognized that it held a number of advantages "over other means of dissemination, including greater speed, greater flexibility and the opportunity to go into considerable detail if necessary". Auger considered reports a "half-published" communication medium with a "complex interrelationship scientific journals". In 1989 Auger published the second edition of "The Documentation of the European Communities: A Guide", which contained the first usage of the term "grey literature" in a published work.