title: [Results of the circular quality control trial of clinical laboratory study results: April 1979].
mesh_terms: D002031:Bulgaria; D019411:Clinical Laboratory Techniques / Q000379:methods / Q000592:standards*; D011786:Quality Control
vernacular_title: Rezultati ot prŭstenovidniia opit za kontrol na kachestvoto na rezultatite ot klinichno-laboratorni izsledvaniia--april 1979.