blogapi_admin_settings in modules/blogapi/blogapi.module
node_form_alter in modules/node/node.module
Implementation of hook_form_alter().
node_menu in modules/node/node.module
Implementation of hook_menu().
taxonomy_form_vocabulary in modules/taxonomy/taxonomy.admin.inc
Display form for adding and editing vocabularies.
user_menu in modules/user/user.module
Implementation of hook_menu().