1. THE EFFECT OF PREGNANCY ON THE SINGING VOICE / EFECTUL SARCINII ASUPRA VOCII CÂNTATE. Authors: TAMÁS J. ALTORJAY, ÁDÁM PERÉNYI , GÁBOR ÁDÁM.2. COMPARISON OF TWO DIFFERENT WARM-UP TASKS, USING A NEW TOOL ALSO. Authors: TAMÁS J. ALTORJAY, CSABA CSÍKOS.3. COMPARISON OF FOUR DIFFERENT WARM-UP TASKS, USING SPECIAL TOOLS ALSO. Authors: TAMÁS J. ALTORJAY, CSABA CSÍKOS.