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tokens: of Galactic anticenter, the kinematic method tends to gain larger distances, which may be caused by the deviation due to noncircular motion (Tian Leahy 2012 ) or the larger uncertainty of the rotation curve in the outer disk in comparison with inner disk due to invalidity of the tangent velocity method. The kinematic method suffers the well-known ambiguity problem as well. Ten estimates derived from the associated objects show the difference with our results on a similar level to the kinematic method. Distance measurements based on RC stars are mainly applicable to the SNRs in the first and fourth quadrants of the Milky Way because RC stars are much less abundant toward Galactic anticenter. So only 3 of 22 SNRs are studied with the RC stars. Two of them (G82.2+5.3 and G109.1–1.0) yielded much larger distances than ours as well as other results, and the estimate to G89.0+4.7 is comparable to ours. Distances derived from the Σ − D relation (seven cases) are much closer to our estimates compared to the results with methods of kinematics and associated objects. The five Sedov estimates all yield distances larger than ours. The three studies based on proper motion or shock velocity provide some informative restrictions on the SNRs in Level B whose distances are not well determined in this study. The detailed analysis of the differences can be found in the Appendix . 4.1.3. Distribution in the Galactic Plane With the measured distances, Figure 9 shows the spatial distribution of 22 SNRs in Level A and B projected on the Galactic plane. Due to the limits of the APOGEE and LAMOST spectroscopic surveys, most of the SNRs under investigation are in the second and third quadrants of the Milky Way. It can be seen that the SNRs are mainly located in the Local arm. Six SNRs are suggested to reside in the Perseus arm. Three cases, i.e., G89.0+4.7, G93.7−0.2, and G94.0+1.0, are found between the two arms. Figure 9. A face-on view of the distribution of the SNRs in Level A (15) and B (7). The red dots and squares with error bars show the measured distances and uncertainties. The black squares are the cases with distance upper limits. The sizes are proportional to their diameters. The background image, created by Robert Hurt in consultation with Robert Benjamin (Churchwell et al. 2009 ), is centered at the Sun, with the Galactic Center in the upward direction. 4.2. The Extinction Curve The extinction curves vary from one sightline to another, revealing the wavelength-dependent extinction law in different environments. As the absolute extinction is usually difficult to measure and uncertain, we use the color excess ratios (CERs), i.e., , to represent the extinction curves for the sightlines to the 32 SNRs, as well as the “ l 165” and the Rosette Nebula. For SNRs whose reddening profiles were well model-fitted, the color excess is then δA in Equation ( 3 )—the amplitude of the extinction jump at a given color. For the other SNRs, we first calculate the color