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  1. Marek Balcerzak, Barnabás Farkas & Szymon Gła̧b (2013). Covering Properties of Ideals. Archive for Mathematical Logic 52 (3-4):279-294.
    Elekes proved that any infinite-fold cover of a σ-finite measure space by a sequence of measurable sets has a subsequence with the same property such that the set of indices of this subsequence has density zero. Applying this theorem he gave a new proof for the random-indestructibility of the density zero ideal. He asked about other variants of this theorem concerning I-almost everywhere infinite-fold covers of Polish spaces where I is a σ-ideal on the space and the set of indices (...)
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  2. Marek Balcerzak & Tomasz Filipczak (2011). On Monotone Hull Operations. Mathematical Logic Quarterly 57 (2):186-193.
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  3. Marek Balcerzak, Andrzej Roslanowski & Saharon Shelah (1998). Ideals Without CCC. Journal of Symbolic Logic 63 (1):128-148.
    Let I be an ideal of subsets of a Polish space X, containing all singletons and possessing a Borel basis. Assuming that I does not satisfy ccc, we consider the following conditions (B), (M) and (D). Condition (B) states that there is a disjoint family F $\subseteq$ P(X) of size c, consisting of Borel sets which are not in I. Condition (M) states that there is a Borel function f: X → X with $f^{-1}[\{x\}] \not\in$ I for each x ∈ (...)
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  4. Marek Balcerzak, Krzysztof Ciesielski & Tomasz Natkaniec (1997). Sierpiński-Zygmund Functions That Are Darboux, Almost Continuous, or Have a Perfect Road. Archive for Mathematical Logic 37 (1):29-35.
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