Bhagchandani L.K., Mehra K.N.

A Saalschutzian theorem for triple series. 10:2 (1969), pp. 319 -- 322.

Bor H.

On absolute summability factors for $|\overline {N}, p_n|_k$ summability. 32:3 (1991), pp. 435 -- 439.

Cassens P., Regan F.

On generalized Lambert summability. 11:4 (1970), pp. 829 -- 839.

Vojtáš P.

Set-theoretic characteristics of summability of sequences and convergence of series. 28:1 (1987), pp. 173 -- 183.

Vojtáš P.

More on set-theoretic characteristics of summability of sequences by regular (Toeplitz) matrices. 29:1 (1988), pp. 97 -- 102.