Lothar Piepmeyer

发表

Heiko Harborth, Lothar Piepmeyer, 1996, J. Comb. Theory, Ser. A.

Heiko Harborth, Tibor Bisztriczky, Lothar Piepmeyer, 1991 .

Heiko Harborth, Lothar Piepmeyer, 1993 .