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tokens: is the linear radius of the half-power beam width of the KVN telescope at the distances of two VeLLOs. On the other hand, there are other targets whose infall velocities are smaller than the freefall velocity at the distances comparable to those of these two sources. This indicates that the collapsing radius of the core may not be uniquely determined but variable depending on the physical status of the core. Any further quantitative discussion in comparison of our observations with results predicted by the various models dealing with gas infall motions is beyond the scope of this paper, and we leave this issue for future study. 4.4. Mass Infall Rates and Mass Accretion Rates toward the VeLLOs, and Their Implication In this section, we consider the mass infall rates from the envelopes of the VeLLOs and the mass accretion rates toward the VeLLOs as useful physical quantities to help us understand the physical processes involved in the formation of the VeLLOs from their parent envelopes. The mass infall rates were derived using the infall speeds obtained from our model fitting, with , where ρ 0 is the mean density of the envelope given by and R in is the half of FWHM (16′′) of our observing KVN telescope. It is assumed that the envelope has a uniform density ρ and the infall is spherically symmetric with a speed of V infall . Estimated mass infall rates range from 10 −7 to 10 −5 M ⊙ yr −1 , with a median value of (3.4 ± 1.5) × 10 −6 M ⊙ yr −1 (Table 3 ). The values of κ can be a significant contributor to the uncertainties in the mass and then the mass infall rate, which may vary within a factor of 2 owing to the uncertainty in the value of κ (Ossenkopf Henning 1994 ). We note that line profiles showing an infall asymmetry can be affected by an outflow activity in their shapes if it is strong enough, and thus the infall speed and the mass infall rate that we derived can be affected. We found that 13 out of 15 sources for which infall speeds are derived from their infall asymmetric profiles have possible outflow wings from the CO observations by Kim et al. ( 2019 ), but they are found to be all weak enough not to significantly affect the derived values of infall speed and the mass infall rate. The mass accretion rate can be obtained by using CO observations around the outflow regions. Kim et al. ( 2019 ) made a single-pointing and/or a mapping survey of 68 VeLLOs in CO lines, finding the evidence for outflows over 16 dense cores having the VeLLOs. We found that there are five outflow sources identified from the CO mapping survey for which the mass infall rates were estimated in this study. For these sources, we used the mass accretion rates given by Kim et al. ( 2019 ). We also found that there are eight more outflow sources identified from the single-pointing CO observations for which the mass infall rates were estimated in this study. For these sources we calculated the mass accretion rates using the equation given by Kim et al. ( 2019 ) with