On reflection principles at small uncountable cardinals

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I investigated reflection principles at small uncountable cardinals, in particular, their consistencies and their relationships with infinite combinatorics, forcing axioms and large cardinal axioms. Among other things, the following results were obtained: (1) I clarified how weak square principles are denied by each reflection principle at omega 2. (2) By showing that the forcing axiom MA+ (sigma-closed) does not follow from any variation of stationary reflection principles at omega 2, I clarified the difference between reflection principles and forcing axioms. (3) It was proved that in L there is a correspondence between hierarchies of stationary reflection principles and indescribable cardinals.