Authors
Niya A. Krasteva
Department of Children's Diseases, Medical University – Pleven, Bulgaria
Boiko R. Shentov
Department of Children's Diseases, Medical University – Pleven, Bulgaria
Adelaida L. Ruseva
Department of Clinical Immunology, Allergology and Clinical Laboratory, Medical University – Pleven, Bulgaria
Chaika K. Petrova
Department of Children's Diseases, Medical University – Pleven, Bulgaria
Simeon P. Petkov
Department of Clinical Immunology, Allergology and Clinical Laboratory, Medical University – Pleven, Bulgaria