user: Question: What is the FIS Nordic World Ski Championship years when the winter Olympics took place in 1968?
Columns: ['Winner', 'Country', 'Winter Olympics', 'FIS Nordic World Ski Championships', 'Holmenkollen']
Types: ['text', 'text', 'real', 'real', 'text']
Sample row: ['Hallgeir Brenden', 'Norway', 1956.0, 1956.0, '1956']
SQL:

assistant: SELECT "FIS Nordic World Ski Championships" FROM "Table" WHERE "Winter Olympics" = 1968.0;