Generate a question which can yield the answer mentioned in the input. Generated question must be answered by the answer provided in input, without using any extra knowledge.

Context : Nikola Kalabic (until the start of World War II) worked in Land-registry management in Valjevo.
Answer : World War II
In what war was Nikola Kalabic a combatant?

Context : Jan Happy Pieterse (28 May 1942 - 26 May 2013 in Alberton, Gauteng, South Africa) was a South African boxer.
Answer : 26 May 2013
What is the date of death for Happy Pieterse?

Context : Hawkmistress! is a fantasy novel written by Marion Zimmer Bradley as part of the Darkover series and is set at the end of Ages of Chaos, in the period of Darkover's history known as the Hundred Kingdoms.
Answer : Darkover series
To which series does Hawkmistress! belong?