A. J. Ducci, S. S. V. Zanei, and I. Y. Whitaker, “Nursing workload to verify nurse/patient ratio in a cardiology ICU”, Rev. Esc. Enferm. USP, vol. 42, no. 4, pp. 673–680, Dec. 2008, doi: 10.1590/S0080-62342008000400009.