Information from the Chessbase website:
The Scandinavian has long lost its former exotic status. Thanks to practical success and a number of publications by some players from Hamburg gathered around the several times German champions Matthias Wahls in Germany this opening even managed to gain the reputation of being a rather solid weapon against 1.e4. The Scandinavian - basically these are two different openings after 1. e4 d5 2. exd5 Black can now play 2...Qxd5 or 2...Nf6, and accordingly two different systems arise, and there is hardly any practitioner, who has both moves in his repertoire. Thanks to Curt Hansen, who scrutinized both systems extensively. His study of the current theoretical works is well reflected in his 62 database texts. But he also goes beyond the current state of theory and presents his own research. More than 30 games extensively annotated by the author (there are all in all about 500 annotated games); a real gem are his 12 games in the training mode; 316 questions are posed, and answering them you can reach a maximum number of 924 points.