diff --git a/packages/angular_devkit/build_angular/src/browser/specs/styles_spec.ts b/packages/angular_devkit/build_angular/src/browser/specs/styles_spec.ts
index 9c60146ff913..7da64970b00e 100644
--- a/packages/angular_devkit/build_angular/src/browser/specs/styles_spec.ts
+++ b/packages/angular_devkit/build_angular/src/browser/specs/styles_spec.ts
@@ -570,7 +570,7 @@ describe('Browser Builder styles', () => {
     expect(main).toContain(`url('/base/assets/component-img-absolute.svg')`);
   }, 90000);
 
-  it(`supports bootstrap@4`, async () => {
+  it(`supports bootstrap@4 with full path`, async () => {
     const bootstrapPath = dirname(require.resolve('bootstrap/package.json'));
 
     const overrides = {
@@ -582,6 +582,16 @@ describe('Browser Builder styles', () => {
     await browserBuild(architect, host, target, overrides);
   });
 
+  it(`supports bootstrap@4 with package reference`, async () => {
+    const overrides = {
+      extractCss: true,
+      styles: ['bootstrap/dist/css/bootstrap.css'],
+      scripts: ['bootstrap/dist/js/bootstrap.js'],
+    };
+
+    await browserBuild(architect, host, target, overrides);
+  });
+
   it(`supports inline javascript in less`, async () => {
     const overrides = { styles: [`src/styles.less`] };
     host.writeMultipleFiles({
diff --git a/packages/angular_devkit/build_angular/src/dev-server/index.ts b/packages/angular_devkit/build_angular/src/dev-server/index.ts
index 20be5820390c..2fdda29dad34 100644
--- a/packages/angular_devkit/build_angular/src/dev-server/index.ts
+++ b/packages/angular_devkit/build_angular/src/dev-server/index.ts
@@ -569,7 +569,16 @@ function _addLiveReload(
       // When HMR is enabled we need to add the css paths as part of the entrypoints
       // because otherwise no JS bundle will contain the HMR accept code.
       const normalizedStyles = normalizeExtraEntryPoints(browserOptions.styles, 'styles')
-        .map(style => path.resolve(root, style.input));
+        .map(style => {
+          let resolvedPath = path.resolve(root, style.input);
+          if (!existsSync(resolvedPath)) {
+            try {
+              resolvedPath = require.resolve(style.input, { paths: [root] });
+            } catch {}
+          }
+
+          return resolvedPath;
+        });
       entryPoints.push(...normalizedStyles);
     }
 
diff --git a/packages/angular_devkit/build_angular/src/webpack/configs/common.ts b/packages/angular_devkit/build_angular/src/webpack/configs/common.ts
index 57898cfc8919..de87acfc1f80 100644
--- a/packages/angular_devkit/build_angular/src/webpack/configs/common.ts
+++ b/packages/angular_devkit/build_angular/src/webpack/configs/common.ts
@@ -208,10 +208,14 @@ export function getCommonConfig(wco: WebpackConfigOptions): Configuration {
     'scripts',
   ).reduce((prev: { bundleName: string; paths: string[]; inject: boolean }[], curr) => {
     const { bundleName, inject, input } = curr;
-    const resolvedPath = path.resolve(root, input);
+    let resolvedPath = path.resolve(root, input);
 
     if (!existsSync(resolvedPath)) {
-      throw new Error(`Script file ${input} does not exist.`);
+      try {
+        resolvedPath = require.resolve(input, { paths: [root] });
+      } catch {
+        throw new Error(`Script file ${input} does not exist.`);
+      }
     }
 
     const existingEntry = prev.find(el => el.bundleName === bundleName);
diff --git a/packages/angular_devkit/build_angular/src/webpack/configs/styles.ts b/packages/angular_devkit/build_angular/src/webpack/configs/styles.ts
index dd6bdfab2878..74bde097204f 100644
--- a/packages/angular_devkit/build_angular/src/webpack/configs/styles.ts
+++ b/packages/angular_devkit/build_angular/src/webpack/configs/styles.ts
@@ -7,6 +7,7 @@
  */
 
 import { tags } from '@angular-devkit/core';
+import * as fs from 'fs';
 import * as path from 'path';
 import * as webpack from 'webpack';
 import { WebpackConfigOptions } from '../../utils/build-options';
@@ -58,7 +59,12 @@ export function getStylesConfig(wco: WebpackConfigOptions) {
     const chunkNames: string[] = [];
 
     normalizeExtraEntryPoints(buildOptions.styles, 'styles').forEach(style => {
-      const resolvedPath = path.resolve(root, style.input);
+      let resolvedPath = path.resolve(root, style.input);
+      if (!fs.existsSync(resolvedPath)) {
+        try {
+          resolvedPath = require.resolve(style.input, { paths: [root] });
+        } catch {}
+      }
       // Add style entry points.
       if (entryPoints[style.bundleName]) {
         entryPoints[style.bundleName].push(resolvedPath);