| Top Galactic radiusa | Bottom Galactic radius | Reference |
| kpc | kpc | |
| 7.6 | 5.8 | Vallée ( [32] —Fig. 1) |
| 7.8 | 5.3 | Rand & Lyne ( [33] —Fig. 5) |
| 7.5 | 4.8 | Indrani & Deshpande ( [71] —Fig. 4) |
| 7.4 | 5.1 | Vallée ( [72] —Fig. 4) |
| 5.9 | 4.2 | Brown et al. ( [34] —Fig. 4) |
| 7.2 | 5.8 | Sun et al. ( [42] —Fig. 10a) |
| 7.7 | 5.8 | Noutsos et al. ( [73] —Fig. 7) |
| 8 | 5.6 | Van Eck et al. ( [24] —Fig. 6) |
| 8 | 5.6 | Xu & Han ( [23] —Fig. 4) |
| 7 | 4.6 | Andreasyan et al. ( [35] —abstract) |
| 7.41 ± 0.20 | 5.26 ± 0.18 | Mean and rms (all data) |
| 7.65 ± 0.10 | 5.48 ± 0.13 | Mean and rms (excluding the data from [34] and from [35] |
| 7.58 ± 0.21 | 5.48 ± 0.22 | Mean and rms (all data recently published—since 2008 or later) |