diff --git a/pysvf/pysvf.pyi b/pysvf/pysvf.pyi
index 5fab409..20c4f4b 100644
--- a/pysvf/pysvf.pyi
+++ b/pysvf/pysvf.pyi
@@ -1841,6 +1841,8 @@ class IntervalValue:
     @overload
     def __init__(self, lb: int, ub: int) -> None: ...
     @overload
+    def __init__(self, lb: BoundedInt, ub: BoundedInt) -> None: ...
+    @overload
     def __init__(self, val: int) -> None: ...
     # `__eq__` and `__ne__`'s type annotations are forced as `bool` for all objects,
     # use `type: ignore` so that equality operators in C++ and Python are the same
@@ -1867,8 +1869,8 @@ class IntervalValue:
     def __lshift__(self, bits: int) -> "IntervalValue": ...
     def __rshift__(self, bits: int) -> "IntervalValue": ...
     def equals(self, other: "IntervalValue") -> "IntervalValue": ...
-    def lb(self) -> int: ...
-    def ub(self) -> int: ...
+    def lb(self) -> BoundedInt: ...
+    def ub(self) -> BoundedInt: ...
     def clone(self) -> 'IntervalValue': ...
     def join_with(self, other: 'IntervalValue') -> None: ...
     def meet_with(self, other: 'IntervalValue') -> None: ...
@@ -1995,9 +1997,9 @@ class AbstractState:
     def __str__(self) -> str: ...
 
     @staticmethod
-    def isNullMem(self, addr: int) -> bool: ...
+    def isNullMem(addr: int) -> bool: ...
     @staticmethod
-    def isBlackHoleObjAddr(self, addr: int) -> bool: ...
+    def isBlackHoleObjAddr(addr: int) -> bool: ...
 
 
 class AbstractInterpretation: