Ratio of rotational energy to gravitational energy β_rot vs. core radius. Data for the sources shown are taken from C. L. H. Hull & Q. Zhang (2019) and K. Pattle et al. (2021) except IRAS 18360 (this work). We have investigated those magnetic-detected sources as samples and ultimately selected those with the detection of velocity gradients or rotations, that are L1448 IRS2 (W. Kwon et al. 2019), NGC 1333 IRAS4A (M. Attard et al. 2009), B335 (H.-W. Yen et al. 2019), L1157 (J. J. Tobin et al. 2011; E. Sharma et al. 2020), IRAS 18089 (P. Sanhueza et al. 2021), G327.3 (H. Beuther et al. 2020), G35.2N (K. Qiu et al. 2013), DR 21(OH) (J. M. Girart et al. 2013), G31.41 (J. M. Girart et al. 2009; M. T. Beltrán et al. 2019), and G240.31 (K. Qiu et al. 2014). We note that the values of β_rot in this plot are lower limits, as they are not corrected for inclination.