De Castro, H. C., Santos, A. M., & Arlante, S. M. (1993). A survey of libraries among selected agencies under the Office of the President with implications toward resource sharing.

De Castro, Helen C., Antonio M. Santos, и Salvacion M. Arlante. A Survey of Libraries Among Selected Agencies Under the Office of the President with Implications Toward Resource Sharing. Quezon City : Institute of Library Science, University of the Philippines Diliman, 1993.

De Castro, Helen C., et al. A Survey of Libraries Among Selected Agencies Under the Office of the President with Implications Toward Resource Sharing. 1993.