ASSASSINATION IN VIENNA
by WALTER B. MAASS
180 pages. Scribners. $7.95.
ANSCHLUSS
by DIETER WAGNER
and GERHARD TOMKOWITZ
255 pages. St. Martin's Press. $7.95.
For most Americans, the name Austria conjures up pleasant visions of ski weeks at Innsbruck, Vienna Sachertorte, Salzburg's music. Few people now recall two important events in that country that led up to World War II and betrayed a darker side of the Austrian character. One was the assassination of Austrian Chancellor Engelbert Dollfuss by local Nazis in 1934, part of a coup that failed. The other, which so dramatically succeeded, was...