Season 2
2x04: Sleepless
2x05: Duane Barry
2x06: Ascension
2x25: Anasazi

Season 3
3x01: Blessing Way
3x02: Paper Clip
3x15: Piper Maru
3x16: Apocrypha 
 
Season 4
4x09: Tunguska
4x10: Terma

Season 5
5x13: Patient X
5x14: The Red & The Black
5x20: The End

Season 9
9x19/20: The Truth

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