@article{Reference1,
Abstract = {We have developed an enhanced Littrow configuration extended cavity diode laser (ECDL) that can be tuned without changing the direction of the output beam. The output of a conventional Littrow ECDL is reflected from a plane mirror fixed parallel to the tuning diffraction grating. Using a free-space Michelson wavemeter to measure the laser wavelength, we can tune the laser over a range greater than 10 nm without any alteration of alignment.},
Author = {C. J. Hawthorn and K. P. Weber and R. E. Scholten},
Journal = {Review of Scientific Instruments},
Month = {December},
Number = {12},
Numpages = {3},
Pages = {4477--4479},
Title = {Littrow Configuration Tunable External Cavity Diode Laser with Fixed Direction Output Beam},
Volume = {72},
Url = {http://link.aip.org/link/?RSI/72/4477/1},
Year = {2001}}

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test.  citet{Reference1}  cite{Reference1} citet*{1.01} citet{Reference2}       citet{Reference3}

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