Question: What is the date of death of Georg Josef Riedel's father?
Sentence (from "Claus Josef Riedel"): He was among the first glassware experts in history to recognize that the taste of wine is affected by the shape of the glass from which it is consumed, and is credited with first discovering the concept of variety-specificity in glassware, developing variety-specific glassware shapes and bringing these glasses to the consumer market.
Relevant evidence: No