Classification of the maximal arithmetic subgroups of indefinite orthogonal groups of type $(B_l)$

An explicit classification is obtained for the maximal arithmetic subgroups of indefinite orthogonal $K$-groups of type $(B_l)$, where $K$ is a global field $(\operatorname{char}K\ne2)$. As a preliminary, a local analogue of the maximality problem is considered, and conditions are determined under which, for groups of the type indicated, local maximality implies global.
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