From: Spatial gradients of geomagnetic temporal variations causing the instability of inter-station transfer functions
\(m =\) BMT
\(m =\) KAK
\(m =\) KNY
\(m =\) MMB
\({\text{BR}}_{m,y} \left( 2 \right)\)
15.5
11.1
8.7
\({\text{BR}}_{m,y} \left( 6 \right)\)
2.1
5.8
4.0
8.5