TY  - JOUR
AU  - D. V. Matyukhin
TI  - On positive-definite biquadratic forms that cannot be represented as the sum of squares of bilinear forms
JO  - Vestnik Moskovskogo universiteta. Matematika, mehanika
PY  - 1995
SP  - 29
EP  - 33
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/VMUMM_1995_2_a5/
LA  - ru
ID  - VMUMM_1995_2_a5
ER  -