E.O.  Effanga, J.A.  Ugboh, E.I.  Enang, B.E.A.  Eno, 
    A Tool for Constructing Pair-Wise Balanced Incomplete Block Designs,
    Journal of Modern Mathematics and Statistics,
    Volume 3,Issue 4,
    2009,
    Pages 69-72,
    ISSN 1994-5388,
    jmmstat.2009.69.72,
    (https://makhillpublications.co/view-article.php?doi=jmmstat.2009.69.72)
    Abstract: This study deals with the construction of Pair-wise 
        Balanced Incomplete Block Designs (PBIBD). We developed a non-linear non-preemptive 
        binary integer goal programming model for the construction of PBIBD for 
        any set of parameters (b, k, t, r, λ). The model so developed is 
        tested using two set of parameters (b = 4, k = 4, t = 3, r = 3, λ 
        = 2) and (b = 7, k = 7, t = 3, r = 3, λ = 1). It is shown that the 
        PBIBD is not unique for any given set of parameters and that the design 
        obtained by our model is D-optimal.
    Keywords: Goal programming;non-linear;non-preemptive;design matrix;information matrix;D-optimal