Mood States Modulate Activity in Semantic Brain Areas during Emotional Word Encoding
M. Kiefer, S. Schuch, W. Schenck, K. Fiedler, Cerebral Cortex 17 (2007) 1516–1530.

Emotion and memory: Event-related potential indices predictive for subsequent successful memory depend on the emotional mood state
M. Kiefer, S. Schuch, W. Schenck, K. Fiedler, Advances in Cognitive Psychology 3 (2007) 363–373.