Oh, I forgot to ask just one more thing: Is there any special requirements for double/multiple entry visa, i.e., an invitation letter,etc. ? Can I just use the following three documents to apply for a double/multiple entry visa?

1. The original Passport with blank visa pages and at least 6-month validity.
2. One properly completed Visa Application Form. American citizens are required to fill in two Visa Application Forms.
3. One recent passport photo attached on the Visa Application Form. American citizens need to offer two photos.

Thanks so much.

Kath