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Valdis I.Jonsdottir, Leena Rantala, Anne-Maria Laukkanen, Erkki Vilkman: Effects of sound amplification on teachers’ speech while teaching. Logopedics Phoniatrics Vocology, 2001; 26:3:118-123.
Valdís I. Jonsdottir: Cordless amplifying systems in classrooms. A descriptive study of teachers’ and students’ opinions. Logopedics Phoniatrics Vocology, 2002; 27:1: 29-36.
Valdis I.Jonsdottir, Anne-Maria Laukkanen, Erkki Vilkman: Changes in teachers’ speech during a working day with and without electric sound amplification. Folia Phoniatrica et Logopaedica, 2002: 54: 6: 282-287.
Valdis I.Jonsdottir VI, Boyle B, Martin PJ, Sigurdardottir G. A comparison of the occurence and nature of vocal symptoms in two groups of Icelandic teachers. Logopedics Phoniatrics Vocology 2002; 27:3: 98 – 105
Valdis I. Jónsdóttir, Anne-Maria Laukkanen, Iilona Siikki: Changes in teachers’voice quality during a working day with and without electric sound amplification. Folia Phoniatrica et Logopaedica, 2003: 55:5:267-280.