A Remark Concerning the Paper "On the Diophantine Equation Ax4 -By2 = C (C = 1, 4)". W. Ljunggren — 1968 Mathematica Scandinavica
New theorems concerning the diophantine equation x 2 + D = 4 y q W. Ljunggren — 1972 Acta Arithmetica
On the representation of integers by certain binary cubic and biquadratic forms W. Ljunggren — 1971 Acta Arithmetica
Diophantine Analysis Applied to Virus Structure. W. Ljunggren; N.G. Wrigley; V. Brun — 1974 Mathematica Scandinavica