AlpertR.HaberR. N.Anxiety in academic achievement situations. Journal of Personality and Social Psychology, 1960, 61, 207–215.
2.
EbelR. L.Essentials of educational measurement. Englewood Cliffs, N.J.: Prentice-Hall, 1972.
3.
SarasonS. B.MandlerG.CraighillP. G.The effects of differential instructions on anxiety and learning. Journal of Abnormal and Social Psychology, 1952, 47, 561–565.