## Abstract

International investing is the strategy of selecting globally based investment instruments as a part of an investment portfolio. In order to diversify the portfolios and enhance growth opportunities, more and more firms choose to invest on foreign stocks and derivatives that bring not only stock price risk, but also the exchange rate risk. This paper considers foreign derivatives in an uncertain financial market. Under the assumption that both the exchange rate and the stock price follow uncertain differential equations, the domestic prices of foreign European options, American options and Asian options are developed by means of contour process, respectively. Some examples are finally provided to further demonstrate the properties of the pricing formulas.

### Keywords

International investing Contour process Uncertain stock model Uncertain currency model## Notes

### Acknowledgements

This work was supported by National Natural Science Foundation of China under Grant No. 61374082, Distinguished Young Scholar Project of Renmin University of China and China Scholarship Council under Grant No. 201606365008.

### Compliance with ethical standards

### Conflict of interest

The authors declare that they have no conflict of interest.

### Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

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