@article{Clette:5770,
      author        = "Clette, Frédéric and Bechet, Sabrina and Lemaître,
                       Olivier and Lefèvre, Laure and Boulvin, Olivier and
                       Vandekerckhove, Joan and Bhattacharya, Shreya and Vanden
                       Broeck, Grégory",
      title         = "{USET daily sunspot drawings (photosphere)}",
      year          = "2021",
}