  This paper presents an up-to-date and refined version of the SCL calculus for
first-order logic without equality. The refinement mainly consists of the
following two parts: First, we incorporate a stronger notion of regularity into
SCL(FOL). Our regularity definition is adapted from the SCL(T) calculus. This
adapted definition guarantees non-redundant clause learning during a run of
SCL. However, in contrast to the original presentation, it does not require
exhaustive propagation. Second, we introduce trail and model bounding to
achieve termination guarantees. In previous versions, no termination guarantees
about SCL were achieved. Last, we give rigorous proofs for soundness,
completeness and clause learning guarantees of SCL(FOL) and put SCL(FOL) into
context of existing first-order calculi.
