TY  - RPRT
TI  - The empty delta sign.
AU  - Satoru Yoshida
AU  - Mitsuo Shidoh
PY  - 2003
DO  - 10.1212/wnl.60.1.146
UR  - https://pubmed.ncbi.nlm.nih.gov/12525742/
ID  - 12525742
ER  -