On Covariant Quantization of the Massive Self-dual 3-forms in 7 Dimensions

Massive self-dual 3-forms in 7 dimensions are analyzed from the point of view of the Hamiltonian path integral quantization. The quantization procedure relies on the quantization of a first-class system equivalent with the original theory. The first-class system is constructed in the framework of gauge unfixing approach and Batalin-Fradkin method. The Hamiltonian path integral of the first-class system takes a manifestly Lorentz-covariant form.