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1. https://slideplayer.com/slide/15720788/
2. https://journals.aps.org/prd/abstract/10.1103/PhysRevD.95.074036
3. https://inspirehep.net/literature/684394 (first measurement HERMES)

Boer-Mulders references:

1) https://arxiv.org/abs/2004.02117 : New study of the Boer-Mulders function: Implications for the quark and hadron transverse momenta (2020)
2) https://arxiv.org/abs/0803.1692 : Extracting Boer-Mulders functions from Deuteron Drell-Yan processes (2008)

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