Combined optical trapping and single-molecule fluorescence. Lang, M.J., Fordyce, P.M., & Block, S.M. Journal of Biology (2003).
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Stepping and stretching: how kinesis uses external strain to step processively. Rosenfeld, S.S., Fordyce, P.M., Jefferson, G.M., King, P.H., & Block, S.M. Journal of Biological Chemistry (2003).