title: Comment on "direct measurement of the oscillation frequency in an optical-tweezers trap by parametric excitation".
authors.affiliation: Danish Polymer Centre, BIO-313 RISØ, Technical University of Denmark DK-4000 Roskilde, Denmark.
authors.forename: Lykke
authors.initials: L
authors.lastname: Pedersen
authors.forename: Henrik
authors.initials: H
authors.lastname: Flyvbjerg