Kucukcifci, Selda, Lindner C.C. The metamorphosis of λ-fold block designs with block size four into λ-fold (K4 \ e)-systems, λ ≥ 2. A Canadian journal of applied mathematics, computer science and statistics [Internet]. 2003 May 9 [cited 2026 May 8];63. Available from: https://utilitasmathematica.com/index.php/Index/article/view/295