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Castelletto, S.
, Degiovanni, I.
, Migdall, A.
and Schettini, V.
(2005),
Spatial and spectral mode selection of heralded single photons from Parametric Down-Conversion in bulk and PPLN, ed. by R.E. Myers and Y. Shih, Proc Quantum Communications and Quantum Imaging III Page SPIE, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=104355
(Accessed October 15, 2025)