remove empty bibliography

content/zettels/optical_fibers.md

@@ -31,9 +31,3 @@ Otherwise, APC connectors are used.
 ## Multi-mode and Single-mode fibers {#multi-mode-and-single-mode-fibers}
 
 If laser is used (fiber interferometer for instance), a single-mode fiber should be used and the wavelength of the mode should be matched with the wavelength of the laser.
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-## Bibliography {#bibliography}
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-<style>.csl-entry{text-indent: -1.5em; margin-left: 1.5em;}</style><div class="csl-bib-body">
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