In this paper, we study typical ranks of 3-tensors and show that there are
plural typical ranks for m x n x p tensors over the real number field in the
following cases. (1) 2<m<5, 4|n and (m-1)(n-1)<p<(m-1)n+1. (2) 4<m<9, 8|n and
(m-1)(n-1)<p<(m-1)n+1. (3) m=9, 16|n and $8n-8<p<8n+1. (4) For some integer s
with s>4, 9<m<2s+1, 2^s|n and (m-1)(n-1)<p<(m-1)n+1. (5) m=3, 4|(n-3) and
p=2n-1. (6) m=4, 4|(n-2), n>5 and p=3n-2. (7) m=6, 8|(n-4), n>11 and p=5n-4.