Measurements of the Nuclear Polarisation of Optically Pumped ${^{3}}$He Atoms Using a ${^{4}}$He Magnetometer E. Noël, H. Gilles, J. Hamel, O. Moreau et B. Chéron J. Phys. III France, 6 8 (1996) 1127-1132 DOI: 10.1051/jp3:1996172