1. He, B., Patel, M., Zhang, Z.: Accessing the Deep Web: A survey. Communications of the ACM 50(5) (2007)
2. Madhavan, J., Afanasiev, L., Antova, L., Halevy, A.Y.: Harnessing the Deep Web: Present and Future. In: CIDR 2009 (2009)
3. Wu, P., Wen, J.-R., Liu, H., Ma, W.-Y.: Query Selection Techniques for Efficient Crawling of Structured Web Sources. In: ICDE 2006 (2006)
4. Raghavan, S., Garcia-Molina, H.: Crawling the Hidden Web. In: VLDB 2001, pp. 129–138 (2001)
5. Lu, J., Wang, Y., Liang, J., Chen, J., Liu, J.: An Approach to Deep Web Crawling by Sampling. In: Web Intelligence 2008 (2008)