For a debate on this meaning and use see:
Brownstein, K. R. (1997). «Angles—Let's treat them squarely». American Journal of Physics. 65 (7). 605 páginas. doi:10.1119/1.18616,
Romain, J.E. (1962). «Angles as a fourth fundamental quantity». Journal of Research of the National Bureau of Standards-B. Mathematics and Mathematical Physics. 66B (3). 97 páginas,
LéVy-Leblond, Jean-Marc (1998). «Dimensional angles and universal constants». American Journal of Physics. 66 (9). 814 páginas. doi:10.1119/1.18964, and Romer, Robert H. (1999). «Units—SI-Only, or Multicultural Diversity?». American Journal of Physics. 67. 13 páginas. doi:10.1119/1.19185
