diff --git a/types/rx-lite/index.d.ts b/types/rx-lite/index.d.ts
index 331145e0dd..16646b0473 100644
--- a/types/rx-lite/index.d.ts
+++ b/types/rx-lite/index.d.ts
@@ -327,21 +327,21 @@ declare namespace Rx {
 
         /**
          * Projects each notification of an observable sequence to an observable sequence and merges the resulting observable sequences into one observable sequence.
-         * @param {Function} onNext A transform function to apply to each element; the second parameter of the function represents the index of the source element.
-         * @param {Function} onError A transform function to apply when an error occurs in the source sequence.
-         * @param {Function} onCompleted A transform function to apply when the end of the source sequence is reached.
-         * @param {Any} [thisArg] An optional "this" to use to invoke each transform.
-         * @returns {Observable} An observable sequence whose elements are the result of invoking the one-to-many transform function corresponding to each notification in the input sequence.
+         * @param onNext A transform function to apply to each element; the second parameter of the function represents the index of the source element.
+         * @param onError A transform function to apply when an error occurs in the source sequence.
+         * @param onCompleted A transform function to apply when the end of the source sequence is reached.
+         * @param [thisArg] An optional "this" to use to invoke each transform.
+         * @returns An observable sequence whose elements are the result of invoking the one-to-many transform function corresponding to each notification in the input sequence.
          */
         selectManyObserver<T2, T3, T4>(onNext: (value: T, index: number) => Observable<T2>, onError: (exception: any) => Observable<T3>, onCompleted: () => Observable<T4>, thisArg?: any): Observable<T2 | T3 | T4>;
 
         /**
          * Projects each notification of an observable sequence to an observable sequence and merges the resulting observable sequences into one observable sequence.
-         * @param {Function} onNext A transform function to apply to each element; the second parameter of the function represents the index of the source element.
-         * @param {Function} onError A transform function to apply when an error occurs in the source sequence.
-         * @param {Function} onCompleted A transform function to apply when the end of the source sequence is reached.
-         * @param {Any} [thisArg] An optional "this" to use to invoke each transform.
-         * @returns {Observable} An observable sequence whose elements are the result of invoking the one-to-many transform function corresponding to each notification in the input sequence.
+         * @param onNext A transform function to apply to each element; the second parameter of the function represents the index of the source element.
+         * @param onError A transform function to apply when an error occurs in the source sequence.
+         * @param onCompleted A transform function to apply when the end of the source sequence is reached.
+         * @param [thisArg] An optional "this" to use to invoke each transform.
+         * @returns An observable sequence whose elements are the result of invoking the one-to-many transform function corresponding to each notification in the input sequence.
          */
         flatMapObserver<T2, T3, T4>(onNext: (value: T, index: number) => Observable<T2>, onError: (exception: any) => Observable<T3>, onCompleted: () => Observable<T4>, thisArg?: any): Observable<T2 | T3 | T4>;
 
@@ -426,7 +426,7 @@ declare namespace Rx {
          * @since 2.2.28
          * @param selector Selector to invoke for every item in the current subscription.
          * @param [thisArg] An optional context to invoke with the selector parameter.
-         * @returns {An exclusive observable with only the results that happen when subscribed.
+         * @returns An exclusive observable with only the results that happen when subscribed.
          */
         exclusiveMap<I, R>(selector: (value: I, index: number, source: Observable<I>) => R, thisArg?: any): Observable<R>;