Usage metrics versus altmetrics: confusing terminology?

Wolfgang Glänzel, Juan Gorraiz. Usage metrics versus altmetrics: confusing terminology?. Scientometrics, 102(3):2161-2164, 2015. [doi]

@article{GlanzelG15,
  title = {Usage metrics versus altmetrics: confusing terminology?},
  author = {Wolfgang Glänzel and Juan Gorraiz},
  year = {2015},
  doi = {10.1007/s11192-014-1472-7},
  url = {http://dx.doi.org/10.1007/s11192-014-1472-7},
  researchr = {https://researchr.org/publication/GlanzelG15},
  cites = {0},
  citedby = {0},
  journal = {Scientometrics},
  volume = {102},
  number = {3},
  pages = {2161-2164},
}