Input: See this dialog response. The 2017 event was Langer's third Senior Open Championship title and his tenth senior major championship victory. What came before?
Came before: DIALOG:
What is the 2017 Senior Open Championship?
- 2017 Senior Open Championship The 2017 Senior Open Championship was a senior major golf championship and the 31st Senior Open Championship, held from 27–30 July at Royal Porthcawl Golf Club in Porthcawl, Wales.
- Are there any other interesting aspects about this article?
- It was the 2nd Senior Open Championship played at the course and the 15th Senior Open Championship played as a senior major championship.
- Who won the championship?
- World Golf Hall of Fame member Bernhard Langer won by three strokes over Corey Pavin.
- Was there anything else significant about the win?
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Input: See this dialog response. Psychedelic Underground Psychedelic Underground is a 1969 psychedelic rock album by the German band Amon Düül. What came before?
Came before: DIALOG:
What was the Psychedelic Underground's debut album?
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Input: See this dialog response. Established in 1993 in an effort to eliminate confusion regarding diagnoses, the WHO system established a four-tiered histologic grading guideline for astrocytomas that assigns a grade from 1 to 4, with 1 being the least aggressive and 4 being the most aggressive. What came before?
Came before:
DIALOG:
What are the different WHO grading systems?
- Of numerous grading systems in use for the classification of tumor of the central nervous system, the World Health Organization (WHO) grading system is commonly used for astrocytoma.
- When was the grading system first established?
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