. Haynes, S. T. Hedetniemi, P. J. Slater, Fundamentals of Domination in Graphs , Marcel Dekkar, Inc., 1997.
 W. Imrich, S. Klavzar, Product Graphs; Structure and Recognition , John Wiley and Sons, New York., 2000.
 W. Imrich, S. Klavzar, D. F. Rall, Topics in Graph Theory: Graphs and their Cartesianproduct , A. K. Peters, Ltd., Wellesley, 2008.
 M. S. Jacobson, L. F. Kinch, On the domination number of products of a graph; I , Ars Comb., vol. 10, 1983, 33-44.
 T. R. Jensen, B. Toft, Graph Coloring Problem , John Wiley & Sons, Inc
First, we define in Mizar , the Cartesian product of two filters bases and the Cartesian product of two filters. After comparing the product of two Fréchet filters on ℕ (F1) with the Fréchet filter on ℕ × ℕ (F2), we compare limF₁ and limF₂ for all double sequences in a non empty topological space.
Endou, Okazaki and Shidama formalized in  the “convergence in Pringsheim’s sense” for double sequence of real numbers. We show some basic correspondences between the p-convergence and the filter convergence in a topological space. Then we formalize that the double sequence converges in “Pringsheim’s sense” but not in Frechet filter on ℕ × ℕ sense.
In the next section, we generalize some definitions: “is convergent in the first coordinate”, “is convergent in the second coordinate”, “the lim in the first coordinate of”, “the lim in the second coordinate of” according to , in Hausdorff space.
Finally, we generalize two theorems: (3) and (4) from  in the case of double sequences and we formalize the “iterated limit” theorem (“Double limit” , p. 81, par. 8.5 “Double limite”  (TG I,57)), all in regular space. We were inspired by the exercises (2.11.4), (2.17.5)  and the corrections B.10 .
Kazuhisa Ishida, Yasunari Shidama and Adam Grabowski
chain-complete posets. Formalized Mathematics, 18(1):47-51, 2010. doi:10.2478/v10037-010-0006-x.
 Artur Korniłowicz. Cartesianproducts of relations and relational structures. Formalized Mathematics, 6(1):145-152, 1997.
 Andrzej Trybulec. Domains and their Cartesianproducts. Formalized Mathematics, 1(1): 115-122, 1990.
 Andrzej Trybulec. Tuples, projections and Cartesianproducts. Formalized Mathematics, 1(1):97-105, 1990.
 Wojciech A. Trybulec and Grzegorz Bancerek. Kuratowski - Zorn
Yuichi Futa, Hiroyuki Okazaki and Yasunari Shidama
Czesław Byliński. Some basic properties of sets. Formalized Mathematics , 1( 1 ):47-53, 1990.
Daniele Micciancio and Shafi Goldwasser. Complexity of lattice problems: A cryptographic perspective (the international series in engineering and computer science). 2002.
Christoph Schwarzweller. The binomial theorem for algebraic structures. Formalized Mathematics , 9( 3 ):559-564, 2001.
Andrzej Trybulec. Domains and their Cartesianproducts. Formalized