TY  - RPRT
TI  - Designing and testing self-help interventions.
AU  - L O Walker
AU  - M K Sandor
AU  - D Sands
PY  - 1989
DO  - 10.1016/s0897-1897(89)80055-2
UR  - https://pubmed.ncbi.nlm.nih.gov/2719491/
ID  - 2719491
ER  -