; (2) shall be provided as an electronic reference guide available to the public free of charge; and (3) may include— (A) available examples of local governments engaging private sector entities in order to implement smart city or community solutions, including public-private partnership models, that could be used to leverage private sector funding and reduce transportation costs; (B) best practices and lessons learned from technology demonstrations, including return on investment and performance information to help cities decide how to initiate integration of smart technologies; (C) voluntary, industry-led, international consensus standards and best practices, in collaboration with the National Institute of Standards and Technology, for safeguarding cybersecurity and appropriate data management and data privacy; and (D) such other topics as are determined to be necessary by the Secretaries. (c) Existing guides In creating, publishing, and maintaining the guide under subsection (a), the Secretaries shall consider Federal guides published before, on, or after the date of enactment of this Act relating to smart city or community goals, activities, and best practices— (1) to prevent duplication of efforts by the Federal Government; and (2) to leverage existing complementary efforts. 5. Smart Cities Challenge Grant Extension Program (a) In general Not later than 12 months after the date of enactment of this Act, the Secretary of Transportation shall develop and implement an additional round to the Smart Cities Challenge under which the Secretary shall provide grants on a competitive basis to small- and medium-sized communities to implement smart transportation proposals. (b) Eligibility To be eligible to receive a grant under this section, an entity shall be— (1) a State or local government; (2) a tribal government; (3) a transit agency or authority; (4) a public toll authority; (5) a metropolitan planning organization; (6) any other subdivision of a State or local government