RtlIsNormalizedString - NtDoc

#ifndef _NTRTL_H
#if (PHNT_VERSION >= PHNT_VISTA)

NTSYSAPI
NTSTATUS
NTAPI
RtlIsNormalizedString(
    _In_ ULONG NormForm, // RTL_NORM_FORM
    _In_ PCWSTR SourceString,
    _In_ LONG SourceStringLength,
    _Out_ PBOOLEAN Normalized
    );

#endif
#endif
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