Dadan Prayogo, Bernadus Sadu, Utomo Wicaksono and Fitri Gunawati 2022. ADDITION OF DEEP CROSS-FRICTION MASSAGE IS BETTER THAN SLOW STROKE BACK MASSAGE AFTER MCKENZIE EXERCISE TO IMPROVE FUNCTIONAL ABILITY AND WORK PRODUCTIVITY OF STONE BREAKERS WITH NON-SPECIFIC LOW BACK PAIN . International Journal of Social Science. 2, 2 (Aug. 2022), 1483–1490. DOI:https://doi.org/10.53625/ijss.v2i2.3080.