diff --git a/public/js/calculators.js b/public/js/calculators.js
index 71601fa..a5d423d 100644
--- a/public/js/calculators.js
+++ b/public/js/calculators.js
@@ -1609,7 +1609,7 @@
           '<div class="calc-result-item"><div class="calc-result-label">75th %ile</div><div class="calc-result-value" style="font-size:16px;color:#f97316;">' + p75.toFixed(1) + '</div><div class="calc-result-sub">High-intermediate</div></div>' +
           '<div class="calc-result-item"><div class="calc-result-label">40th %ile</div><div class="calc-result-value" style="font-size:16px;color:#f59e0b;">' + p40.toFixed(1) + '</div><div class="calc-result-sub">Low-intermediate</div></div>' +
         '</div>' +
-        '<p style="font-size:11px;color:var(--g400);margin:12px 0 0;">Bhutani hour-specific nomogram for infants >= 35 weeks GA. Bhutani et al., Pediatrics 1999.</p>';
+        '<p style="font-size:11px;color:var(--g400);margin:12px 0 0;">Bhutani hour-specific nomogram for infants &ge; 35 weeks GA. Values from Harriet Lane Handbook (Johns Hopkins Children&rsquo;s Center Kids Kard).</p>';
 
       // Chart: Bhutani zone curves with patient
       renderBiliChart(hours, tsb, [