(), , , . :
) nn (.. , .. , Gerlach).
) ;
) Moyers ( Tnak Johnson);
) N. Nance.
) Pont.
) G. Korkhaus.
) .. .
) H. Howes .. .
) Gerlach;
) Fuss.
) .
) Schwarz;
) HawleyHerberHerbst.
. nn (d , ) (. 1).
∑ 4 I
----------------------------- = 1,35 nn,
∑ 4 i
∑ 4 I Md , ∑ 4 i .
d nn. 1,42, labidodontie ( ) Gerlach 1,22.
.. nn 1,33.
nn : ∑ 4 i × 1,35 = ∑ 4 I, ∑ 4 I ∑ Md Md , 2 Md .
: ∑ 4 i = 20,8 . 20,8 × 1,35 = 28,08 Md 4 . 28,08 15,6 ( d ) = 12,48 . 12,48: 2 = 6,24 . , 6,24 d .